<PAGE>
 
                                                                 Exhibit 10.20

 
                             SECOND AMENDMENT TO
                               WARRANT AGREEMENT
                                        

     THIS SECOND AMENDMENT TO WARRANT AGREEMENT (this "Second Amendment") is
made and entered into as of this 22nd day of August, 1997, by and between UNCLE
B'S BAKERY, INC., an Iowa corporation (the "Issuer"), and CREDITANSTALT-
BANKVEREIN, an Austrian banking corporation ("Creditanstalt").

                              W I T N E S S E T H:
                              ------------------- 

     WHEREAS, pursuant to the Loan and Security Agreement dated as of July 12,
1995, between the Issuer and Creditanstalt Corporate Finance, Inc. ("CFI") (the
"Loan Agreement"), CFI made a loan to the Issuer upon the terms set forth in the
Loan Agreement; and

     WHEREAS, in order to induce CFI to structure and to provide the loan
pursuant to the Loan Agreement, the Issuer executed and delivered a Warrant
Agreement dated as of July 12, 1995 (as amended by the First Amendment (as
defined below) and as may be amended, supplemented or otherwise modified from
time to time, the "Warrant Agreement") and issued to CFI Series A Warrants to
purchase 215,000 shares of Common Stock or Convertible Preferred Stock of the
Issuer, which Warrants were later transferred by CFI to Creditanstalt American
Corporation ("CAC"), an affiliate of CFI; and

     WHEREAS, on October 28, 1996, the Issuer and CFI entered into a Waiver and
First Amendment to Loan and Security Agreement which modified certain
definitions and covenants and waived certain defaults, and on November 15, 1996,
the Issuer and CFI entered into a Second Amendment to Loan and Security
Agreement (the "Second Loan Agreement Amendment") to provide for the loan of
additional funds; and

     WHEREAS, in connection with and to induce CFI to enter into the Second Loan
Agreement Amendment, the Issuer amended the Warrant Agreement on November 15,
1996 (the "First Amendment") and issued to CAC Series B Warrants to purchase
205,000 shares of Common Stock or Convertible Preferred Stock of the Issuer; and

     WHEREAS, also on November 15, 1996, CAC made an equity investment in
111,111 shares of Common Stock of the Issuer, which equity investment has been
transferred to Creditanstalt; and

     WHEREAS, the Issuer and CFI wish to enter into a Waiver and Third
Amendment to Loan and Security Agreement dated of even date herewith (as the
same may be amended, supplemented or otherwise modified from time to time, the
"Third Loan Agreement Amendment"); and

     WHEREAS, in connection with and to induce CFI to enter into the Third Loan
Agreement Amendment, the Issuer has agreed to substitute Creditanstalt as the
Warrantholder of 
<PAGE>
 
the Series A Warrants and Series B Warrants, and to amend the Warrant
Agreement, as further set forth herein, in order to provide for the issuance
of certain additional Warrants to Creditanstalt and make certain other changes
set forth herein;

     NOW, THEREFORE, in consideration of these premises, the terms and
conditions herein, and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto hereby agree
as follows:

     Section 1. Definitions. As used in this Second Amendment, unless
otherwise defined herein, terms defined in the Warrant Agreement and the First
Amendment shall have the meaning set forth therein when used herein.

     Section 2.  Amendment of Definition of "Closing Date".  The term "Closing
Date," as set forth in Section 1 of the Warrant Agreement, is hereby deleted in
its entirety and the following definition is substituted in lieu thereof:

              "Closing Date" shall mean (i) with respect to the Series A
          Warrants, July 12, 1995, (ii) with respect to the Series B Warrants
          and the Purchased Shares, November 15, 1996, and (iii) with respect
          to the Series C Warrants, August 22, 1997.

     Section 3.  Amendment of Definition of "Convertible Preferred Stock".  The
term "Convertible Preferred Stock," as set forth in Section 1 of the Warrant
Agreement, is hereby deleted in its entirety and the following definition is
substituted in lieu thereof:

              "Convertible Preferred Stock" shall mean the Class B Preferred
          Stock, Series 3 of the Issuer, par value $.01 per share, which shall
          be convertible into Common Stock of the Issuer, and shall include
          any stock into which such Convertible Preferred Stock shall have
          been changed or any stock resulting from any reclassification of
          such Convertible Preferred Stock.

     Section 4.  Deletion of Definition of "Exchange Right".  The term "Exchange
Right," as set forth in Section 1 of the Warrant Agreement, is hereby deleted in
its entirety.

     Section 5. Amendment of Definition of "Exercise Price". The term
"Exercise Price," as set forth in Section 1 of the Warrant Agreement, is
hereby deleted in its entirety and the following definition is substituted in
lieu thereof:

              "Exercise Price" shall mean the exercise price of a Warrant,
          which shall be $0.55 per Warrant.

     Section 6.  Amendment of Definition of "Expiration Date".  The term
"Expiration Date," as set forth in Section 1 of the Warrant Agreement, is hereby
deleted in its entirety and the following definition is substituted in lieu
thereof:

                                       2
<PAGE>
 
              "Expiration Date" shall mean (i) with respect to the Series A
          Warrants, July 12, 2005, (ii) with respect to the Series B Warrants,
          November 15, 2006, and (iii) with respect to the Series C Warrants,
          August 22, 2007.

     Section 7. Definitions of "Mandatory Exchange" and "Mandatory Redemption".
Section 1 of the Warrant Agreement is hereby amended by adding following the
definition of "Expiration Date," new definitions of "Mandatory Exchange" and
"Mandatory Redemption" as follows:

              "Mandatory Exchange" shall have the meaning given to such term
          in subsection 16(b).

              "Mandatory Redemption" shall have the meaning given to such term
          in subsection 16(a)(i).

     Section 8. Definition of "Series C Warrants". Section 1 of the Warrant
Agreement is hereby amended by adding following the definition of "Series B
Warrants," a new definition of "Series C Warrants" as follows:

              "Series C Warrants" shall mean the stock purchase warrants
          issued pursuant to this Warrant Agreement entitling the record
          holders thereof to purchase from the Issuer at the Warrant Office
          650,000 shares of Common Stock or Convertible Preferred Stock (in
          the percentages and to the extent provided in subsections 6(e) and
          6(f) hereof and subject in each case to adjustments as provided in
          Section 12) at the Exercise Price therefor at any time after August
          22, 1997 and before 5:00 p.m., New York time, on the Expiration Date
          therefor, individually, a "Series C Warrant."

     Section 9. Definition of "Trigger Date". Section 1 of the Warrant
Agreement is hereby amended by adding following the definition of
"Subsidiary," a new definition of "Trigger Date" as follows:

              "Trigger Date" shall have the meaning given to such term in
          subsection 16(a)(i).

     Section 10. Amendment of Definition of "Warrants". The term "Warrants,"
as set forth in Section 1 of the Warrant Agreement, is hereby deleted in its
entirety and the following definition is substituted in lieu thereof:

              "Warrants" shall mean the Series A Warrants, the Series B
          Warrants and the Series C Warrants, collectively; individually, a
          "Warrant."

                                       3
<PAGE>
 
     Section 11. Duration and Exercise of Warrants. Section 6 of the Warrant
Agreement is hereby amended to delete subsection (a) thereof in its entirety
and to substitute therefor a new subsection (a) to read as follows:

              (a)  (i)   The Series A Warrants evidenced by a Series
          A Warrant Certificate shall be exercisable in whole or in part by the
          registered holder thereof on any Business Day after July 12, 1995 and
          on or before 5:00 p.m., New York time, on the Expiration Date
          therefor.

                   (ii)  The Series B Warrants evidenced by a Series B Warrant
          Certificate shall be exercisable in whole or in part by the
          registered holder thereof on any Business Day after November 15,
          1996 and on or before 5:00 p.m., New York time, on the Expiration
          Date therefor.

                   (iii) The Series C Warrants evidenced by a Series C
          Warrant Certificate shall be exercisable in whole or in part by the
          registered holder thereof on any Business Day after August 22, 1997
          and on or before 5:00 p.m., New York time, on the Expiration Date
          therefor.

     Section 12.  Duration and Exercise of Warrants.  Section 6 of the Warrant
Agreement is hereby amended to delete subsections (e) and (f) thereof in their
entirety and to substitute therefor new subsections (e) and (f) to read as
follows:

              (e) At the election of the Warrant Holder made at the time of
          exercise, the Warrant Shares to be issued upon such exercise may be
          either Common Stock or Convertible Preferred Stock (or a combination
          thereof), provided that the Warrant Holder shall not have the right
          to have issued to it upon exercise Common Stock which, when
          aggregated with all other shares of Common Stock (other than shares
          of Non-Attributable Stock) currently or previously held by or
          currently issuable without restriction to the Warrant Holder, will
          exceed 4.99% of the then outstanding Common Stock unless such
          Warrant Holder certifies that such Warrants have previously been
          transferred either (i) in a widely dispersed public offering of the
          Warrants, or (ii) in a private placement in which no purchaser,
          individually or in concert with others, would have acquired more
          than 2% of the outstanding Common Stock if the Warrants so
          transferred had been exercised for Common Stock, or (iii) in
          compliance with Rule 144 (or any rule which is a successor thereto)
          of the Securities Act, or (iv) into the secondary market in a market
          transaction executed through a registered broker-dealer in blocks of
          no more than 2.0% of the shares

                                       4
<PAGE>
 
          outstanding of the Issuer in any six month period; provided further
          that if the Warrant Holder is a bank or an Affiliate of a bank
          subject to the provisions of the Bank Holding Company Act of 1956,
          as amended, such Common Stock, together with all other shares of
          Common Stock currently or previously held by or currently issuable
          without restriction to such Warrant Holder and its Affiliates (not
          including Non-Attributable Stock), will not exceed 4.99% of the then
          outstanding Common Stock. In the event two or more Warrant Holders
          attempt to exercise Warrants for Common Stock simultaneously and, if
          permitted, such exercises would cause the 4.99% limitation to be
          exceeded, then the Issuer shall notify the Warrant Holders who had
          attempted to exercise Warrants for Common Stock and each such
          Warrant Holder shall be entitled to exercise for Common Stock only
          such number of Warrants as shall equal the product of (i) the number
          of Warrants the Warrant Holder sought to exercise for Common Stock
          times (ii) a fraction, the numerator of which is the maximum number
          of Warrants which may be exercised for Common Stock without
          exceeding the 4.99% limitation and the denominator of which is the
          maximum number of Warrants sought to be exercised for Common Stock
          by such Warrant Holders.

              (f) Notwithstanding the foregoing provisions of this Section 6,
          in no event shall any Warrant be exercisable for shares of Common
          Stock or Convertible Preferred Stock which, when aggregated with all
          other shares of capital stock of the Issuer (other than shares of
          Non-Attributable Stock) currently held or previously held by or
          currently issuable without restriction to Creditanstalt or its
          Affiliates, would, upon issuance, represent in excess of 24.99% of
          the Equity of the Issuer unless such shares, when issued, would
          constitute Non-Attributable Stock.

     Section 13.  Restrictions on Transfer.  Section 14 of the Warrant Agreement
is hereby amended by deleting the proviso in the first sentence of subsection
(e) in its entirety and substituting in lieu therefor a new proviso to read as
follows:

          . . . provided, however, that after two (2) years from the date of
          issuance of any Warrants (or such shorter period as may be provided
          by Rule 144(k) promulgated under the Securities Act), such
          restrictions will automatically terminate (without the necessity of
          any opinion of counsel) as to such Warrants and as to any Warrant
          Shares issued in respect of such Warrants upon exercise of the
          Conversion Right set forth in subsection 6(b) above.

                                       5
<PAGE>
 
     Section 14.  Mandatory Redemption and Mandatory Exchange.  Section 16 of
the Warrant Agreement is hereby amended by deleting subsections (a) and (b) in
their entirety and substituting in lieu therefor new subsections (a) and (b)
that shall read as follows:

              (a)  (i)  Subject to the limitations hereinafter set forth, if
          the Issuer takes any action with respect to its capital stock
          (including, without limitation, any purchase of its shares or any
          combination of shares or reverse stock split and elimination of
          fractional shares) which would cause the capital stock currently or
          previously held by or currently issuable without restriction to
          Creditanstalt and its Affiliates (not including Non-Attributable
          Stock) to exceed 24.99% of the Equity of the Issuer, then prior to
          or simultaneously with such action, the Issuer shall purchase from
          Creditanstalt and/or its Affiliates such number of Warrants, Warrant
          Shares or other shares of capital stock as will reduce the shares of
          capital stock currently or previously held by or currently issuable
          without restriction to Creditanstalt and its Affiliates (not
          including Non-Attributable Stock) to 24.99% of the Equity of the
          Issuer (any such mandatory purchase being herein referred to as a
          "Mandatory Redemption"). The price to be paid to the holder upon a
          Mandatory Redemption shall be an amount equal to the Put Price at
          the date the event causing such Mandatory Redemption occurs (the
          "Trigger Date"). The "Put Price" on any such Trigger Date shall be
          the amount which is determined when the Current Market Price Per
          Share of Common Stock on the Trigger Date is multiplied by the
          aggregate number of shares of Common Stock of the Issuer (i)
          comprising the Warrant Shares to be purchased by the Issuer, and/or
          (ii) issuable upon exercise of the Warrants to be purchased by the
          Issuer, and/or (iii) issuable upon conversion of the Convertible
          Preferred Stock comprising the Warrant Shares to be purchased by the
          Issuer, and/or (iv) issuable upon conversion of the Convertible
          Preferred Stock issuable upon exercise of the Warrants to be
          purchased by the Issuer (assuming Convertible Preferred Stock,
          rather than Common Stock, is then issuable under such Warrants),
          and/or (v) comprising any other shares of capital stock of the
          Issuer then held or previously held by Creditanstalt or its
          Affiliates (excluding Non-Attributable Stock).

                   (ii) The completion of all purchases and sales of Warrants,
          Warrant Shares or other shares of capital stock of the Issuer
          pursuant to a Mandatory Redemption shall take place on the thirtieth
          (30th) day following the Trigger Date, unless another date is
          mutually agreed upon by the Issuer and the selling holder (the "Put
          Closing Date"). The Put Prices for all such purchases and sales
          shall be paid by the Issuer to the selling holder in immediately
          available

                                       6
<PAGE>
 
          funds against delivery of certificates representing the Warrants,
          Warrant Shares and/or other shares of capital stock of the Issuer to
          be purchased, duly endorsed for transfer to the Issuer.


                   (b) If the Issuer takes any action with respect to its
          capital stock (including, without limitation, any purchase of its
          shares or any combination of shares or reverse stock split and
          elimination of fractional shares) which would cause the Common Stock
          currently or previously held by or currently issuable without
          restriction to Creditanstalt and its Affiliates (other than shares
          of Non-Attributable Stock) to exceed 4.99% of the aggregate number
          of issued and outstanding shares of Common Stock, then prior to or
          simultaneously with such action, the Issuer shall exchange such
          portion of Common Stock for Convertible Preferred Stock as will
          reduce the shares of Common Stock currently or previously held by or
          currently issuable without restriction to Creditanstalt and its
          Affiliates (not including Non-Attributable Stock) to 4.99% of the
          aggregate number of issued and outstanding shares of Common Stock (a
          "Mandatory Exchange").

     Section 15.  Exhibit A.  The Warrant Agreement is hereby further amended by
deleting Exhibit A thereto in its entirety and by substituting therefore new
Exhibits A-1, A-2 and A-3 in the forms attached as Exhibits A-1, A-2 and A-3
hereto.

     Section 16. Representations and Warranties. The Issuer hereby represents
and warrants to Creditanstalt, for the benefit of Creditanstalt and any other
Warrant Holder, as follows:

              (a) The Issuer is a corporation duly incorporated and validly
     existing under the laws of the State of Iowa, has the corporate power and
     authority to conduct its business as presently conducted and as intended
     to be conducted, has the corporate power and authority to execute and
     deliver this Second Amendment and the Warrant Certificates, to issue the
     Warrants and to perform its obligations under this Second Amendment and
     the Warrant Certificates, has the corporate power and authority and legal
     right to own and lease its properties and is duly qualified and in good
     standing as a foreign corporation in each jurisdiction in which it owns
     or leases real property or in which the conduct of its business requires
     such qualification, except where failure to be so qualified could not be
     reasonably expected to have a material adverse effect on the business,
     properties, financial condition or results of operations of the Issuer
     and its Subsidiaries taken as a whole.

              (b) The execution, delivery and performance by the Issuer of
     this Second Amendment and the Warrant Certificates, the issuance of the
     Warrants and the issuance of the Warrant Shares upon the exercise of the
     Warrants and the issuance of Common Stock upon conversion of the
     Convertible Preferred Stock have been duly authorized by all necessary
     corporate action and do not and will not violate, or result in a breach
     of, or constitute a default under, or require any consent under, or
     result in the creation of any lien, charge or encumbrance upon the assets
     of the Issuer pursuant to, any law, statute, ordinance, rule, regulation,
     order or decree of any court, governmental

                                       7
<PAGE>
 
     body or regulatory authority or administrative agency having jurisdiction
     over the Issuer or its Subsidiaries or the Issuer's Articles of
     Incorporation or any contract, mortgage, loan agreement, note, lease or
     other instrument binding upon the Issuer or its Subsidiaries or by which
     their properties are bound.

              (c) This Second Amendment has been duly executed and delivered
     by the Issuer and constitutes a legal, valid, binding and enforceable
     obligation of the Issuer. When the Warrants and Warrant Certificates have
     been issued as contemplated hereby, (i) the Warrants and the Warrant
     Certificates will constitute legal, valid, binding and enforceable
     obligations of the Issuer and (ii) the Warrant Shares, when issued upon
     exercise of the Warrants in accordance with the terms hereof, and the
     Common Stock, when issued upon conversion of the Convertible Preferred
     Stock in accordance with the terms of the Issuer's Articles of
     Incorporation relating to the Convertible Preferred Stock, will be duly
     authorized, validly issued, fully paid and nonassessable shares of the
     Common Stock and Convertible Preferred Stock, as applicable.

              (d) The Issuer has authorized capital stock consisting of
     40,000,000 Class A shares, par value $.01 per share, of which 3,656,258
     shares are issued and outstanding, and 10,000,000 Class B shares, par
     value $.01 per share, 215,000 shares of which have been designated as
     Series 1 Convertible Preferred Stock, none of which are issued and
     outstanding, 420,000 shares of which have been designated as Series 2
     Convertible Preferred Stock, none of which are issued and outstanding,
     and 1,070,000 shares of which have been designated as Series 3
     Convertible Preferred Stock, none of which are issued and outstanding.
     Except as set forth on SCHEDULE I hereto, there are no outstanding
     options, warrants, subscriptions, rights, convertible or exchangeable
     securities or other agreements or plans under which the Issuer may be or
     become obligated to issue, sell or transfer shares of its capital stock
     of other securities. The Convertible Preferred Stock has no voting
     rights, except as required by law, and is convertible on a share-for-
     share basis into Common Stock of the Issuer. To the Issuer's best
     knowledge, there are no voting agreements, voting trusts, proxies or
     other agreements or understandings with respect to the voting of any
     capital stock of the Issuer or any Subsidiary, other than the Voting
     Agreement between William T. Rose, Jr. and William T. Rose, Sr. dated
     August 14, 1993, the provisions of Section 9(c) of the Warrant Agreement
     as amended hereby, and the provisions of Section 3 of the Subscription
     Agreement dated November 15, 1996 between the Issuer and CAC.

              (e) Except as set forth on SCHEDULE II hereto, no holder of
     securities of the Issuer has any right to the registration of such
     securities under the Securities Act and any applicable state securities
     law.

              (f) The Issuer has filed all proxy statements, reports and other
     documents required to be filed by it under the Exchange Act. The Issuer
     has furnished Creditanstalt with copies of its Report on Form 10-KSB for
     the fiscal year ended July 31, 1996 and copies of its Reports on Form 10-
     QSB for the fiscal quarters ended October 31, 1996, January 31, 1997 and
     April 30, 1997 (the "SEC Reports"). Each SEC Report was in substantial
     compliance with the requirements of its respective form and none of the
     SEC Reports, nor the financial statements (and the notes thereto)
     included in the SEC Reports, as of their respective dates, contained any
     untrue statement of a material fact or

                                       8
<PAGE>
 
     omitted to state a material fact required to be stated therein or
     necessary to make the statements therein, in light of the circumstances
     under which they were made, not misleading.

     Section 17. Expenses. Issuer agrees to pay, immediately upon demand by
Creditanstalt, all costs, expenses, attorneys' fees, and other charges and
expenses incurred by Creditanstalt in connection with the negotiation,
preparation, execution and delivery of this Second Amendment and any other
instrument, document, agreement or amendment executed in connection with this
Second Amendment.

     Section 18. Limitation of Amendment. Except as expressly set forth
herein, this Second Amendment shall not be deemed to waive, amend or modify
any term or condition of the Warrant Agreement, each of which is hereby
ratified and reaffirmed and shall remain in full force and effect, nor to
serve as a consent to any matter prohibited by the terms and conditions
thereof.

      Section 19. Counterparts. This Second Amendment may be executed in any
number of counterparts and any party hereto may execute any counterpart, each
of which when executed and delivered will be deemed to be an original and all
of which, taken together, will be deemed but one and the same agreement.

      Section 20. Governing Law; Jurisdiction. THIS SECOND AMENDMENT, AND THE
RIGHTS AND OBLIGATIONS OF THE PARTIES HEREUNDER, SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK (WITHOUT
REGARD TO THE PRINCIPLES OF CONFLICTS OF LAW).



                  [Remainder of page intentionally left blank]

                                       9
<PAGE>
 
      IN WITNESS WHEREOF, the parties hereto have executed this Second Amendment
under seal as of the date and year first above written.


                                  UNCLE B'S BAKERY, INC.

                                  By: /s/ William T. Rose, Sr.
                                     ----------------------------------------
                                          Name: William T. Rose, Sr.
                                          Title: Executive Vice President


                                  Attest: /s/ William Howard McClellan, Jr.
                                         ------------------------------------
                                          Name: William Howard McClellan, Jr.
                                          Title: Corporate Secretary


                                  CREDITANSTALT-BANKVEREIN

                                  By: /s/ Scott Kray
                                     ----------------------------------------
                                          Name: Scott Kray
                                          Title: Vice President


                                  By: /s/ W. Craig Stamm
                                     ----------------------------------------
                                          Name: W. Craig Stamm
                                          Title: Vice President
<PAGE>
 
                                                                     EXHIBIT A-1

                      FORM OF SERIES A WARRANT CERTIFICATE

THE WARRANTS AND SHARES REPRESENTED BY THIS SERIES A WARRANT CERTIFICATE HAVE
NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY
APPLICABLE STATE SECURITIES LAW AND MAY NOT BE SOLD OR TRANSFERRED IN THE
ABSENCE OF SUCH REGISTRATION OR AN EXEMPTION THEREFROM UNDER SUCH ACT OR LAW.
SUCH WARRANTS AND SHARES MAY BE TRANSFERRED ONLY IN COMPLIANCE WITH THE
CONDITIONS SPECIFIED IN AND ARE SUBJECT TO OTHER PROVISIONS OF THE WARRANT
AGREEMENT, DATED AS OF JULY 12, 1995, (AS AMENDED) BETWEEN THE ISSUER AND
CREDITANSTALT CORPORATE FINANCE, INC., A COMPLETE AND CORRECT COPY OF WHICH IS
AVAILABLE FOR INSPECTION AT THE PRINCIPAL OFFICE OF THE ISSUER AND WILL BE
FURNISHED TO THE HOLDER HEREOF UPON WRITTEN REQUEST AND WITHOUT CHARGE.

THE WARRANTS REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN MANDATORY
REDEMPTION AND EXCHANGE RIGHTS MORE FULLY SET FORTH IN THE WARRANT AGREEMENT.

                                                            Certificate No. A-__
                                                                          [Date]


                         EXERCISABLE ONLY ON OR BEFORE
                                 July 12, 2005

                              Warrant Certificate

     This Series A Warrant Certificate (this "Warrant Certificate") certifies
that Creditanstalt-Bankverein ("Creditanstalt"), or registered assigns, is the
registered holder of 215,000 Warrants (the "Warrants") to purchase Common
Stock or Convertible Preferred Stock of Uncle B's Bakery, Inc., an Iowa
corporation (the "Issuer"). Each Warrant entitles the holder, but only subject
to the conditions set forth herein and in the Warrant Agreement referred to
below, to purchase from the Issuer before 5:00 P.M., New York time, on July
12, 2005 (the "Expiration Date"), one (1) fully paid and nonassessable share
of the Common Stock or Convertible Preferred Stock of the Issuer (the "Warrant
Shares") in the percentages and to the extent set forth in the Warrant
Agreement, at a price (the "Exercise Price") of $0.55 per Warrant payable in
lawful money of the United States of America, upon surrender of this Warrant
Certificate, execution of the annexed Form of Election to Purchase and payment
of the Exercise Price at the office of the Issuer at 441 Dubuque Street,
Ellsworth, Iowa 50075, or such other address as the Issuer may specify in
writing to the registered holder of Warrants evidenced hereby (the "Warrant
Office"). In lieu of exercising Warrants pursuant to the immediately preceding
sentence, the Warrant holder shall have the right to require the Issuer to
convert the Warrants, in whole or in part and at

                                    A-1-1
<PAGE>
 
any time or times, into Warrant Shares, by surrendering to the Issuer the
Warrant Certificate evidencing the Warrants to be converted, accompanied by
the annexed Form of Notice of Conversion which has been duly completed and
signed. The Exercise Price and number of Warrant Shares purchasable upon
exercise of the Warrants are subject to adjustment prior to the Expiration
Date as set forth in the Warrant Agreement. In no event shall this Warrant be
exercisable for shares of Common Stock or Convertible Preferred Stock which,
when aggregated with all other capital stock of the Issuer (other than shares
of Non-Attributable Stock) then held or previously held by or currently
issuable without restriction to Creditanstalt or its Affiliates would, upon
issuance, represent in excess of 24.99% of the Equity of the Issuer (defined
in the Warrant Agreement) unless such shares, when issued, would constitute
Non-Attributable Stock (as defined in the Warrant Agreement).

     No Warrant may be exercised after 5:00 P.M., New York time, on the
Expiration Date and (except as otherwise provided in the Warrant Agreement)
all rights of the registered holders of the Warrants shall cease after 5:00
P.M., New York time, on the Expiration Date.

     The Issuer may deem and treat the registered holders of the Warrants
evidenced hereby as the absolute owners thereof (notwithstanding any notation
of ownership or other writing hereon made by anyone), for the purpose of any
exercise hereof and of any distribution to the holders hereof and for all
other purposes, and the Issuer shall not be affected by any notice to the
contrary.

     Warrant Certificates, when surrendered at the office of the Issuer at the
Warrant Office by the registered holder hereof in person or by a legal
representative duly authorized in writing, may be exchanged, in the manner and
subject to the limitations provided in the Warrant Agreement, but without
payment of any service charge, for another Warrant Certificate or Warrant
Certificates of like tenor evidencing in the aggregate a like number of
Warrants.

     Upon due presentment for registration of transfer of this Warrant
Certificate at the Warrant Office, a new Warrant Certificate or Warrant
Certificates of like tenor and evidencing in the aggregate a like number of
Warrants shall be issued in exchange for this Warrant Certificate to the
transferee(s) and, if less than all the Warrants evidenced hereby are to be
transferred, to the registered holder hereof, subject to the limitations
provided in the Warrant Agreement, without charge except for any tax or other
governmental charge imposed in connection therewith.

     This Warrant Certificate is one of the Warrant Certificates referred to
in the Warrant Agreement, dated as of July 12, 1995, (as amended) between the
Issuer and Creditanstalt Corporate Finance, Inc.. Said Warrant Agreement is
hereby incorporated by reference in and made a part of this instrument and is
hereby referred to for a description of the rights, limitation of rights,
obligations, duties and immunities thereunder of the Issuer and the holders.

                                    A-1-2
<PAGE>
 
     IN WITNESS WHEREOF the Issuer has caused this Warrant Certificate to be
signed by its duly authorized officers and has caused its corporate seal to be
affixed hereunto.


ATTEST:                             UNCLE B'S BAKERY, INC.

__________________________          By:__________________________

________________, Secretary           ________________, President


[Corporate Seal]

                                    A-1-3
<PAGE>
 
                                                          ANNEX to Form
                                                          of Series A Warrant
                                                          Certificate

                          FORM OF ELECTION TO PURCHASE

                   (To be executed upon exercise of Warrant)

     The undersigned hereby irrevocably elects to exercise the right,
represented by this Warrant Certificate, to purchase ____________ Warrant
Shares* and herewith tenders payment for such Warrant Shares to the order of
the Issuer in the amount of $_____________ in accordance with the terms
hereof. The undersigned requests that a certificate for such Warrant Shares be
registered in the name of __________________ whose address is ______________
and that such certificate be delivered to ___________________ whose address is
________________. If said number of Warrant Shares is less than all of the
Warrant Shares purchasable hereunder, the undersigned requests that a new
Warrant Certificate representing the remaining balance of the Warrant Shares
be registered in the name of ____________________ whose address is
______________________ and that such Warrant Certificate be delivered to
________________ whose address is _____________________.

Signature:


__________________________________________
(Signature must conform in all respects to name of holder as specified on the
face of the Warrant Certificate.)


Date:_____________


*    Consisting of:

          _____ shares of Common Stock

          _____ shares of Convertible Preferred Stock


                                    A-1-4
<PAGE>
 
                                                  ANNEX to Form
                                                  of Series A Warrant
                                                  Certificate

                          FORM OF NOTICE OF CONVERSION

                  (To be executed upon conversion of Warrant)


     The undersigned hereby irrevocably elects to exercise the right,
represented by this Warrant Certificate, to convert Warrants represented
hereby into ________________________ Warrant Shares* in accordance with the
terms hereof. The undersigned requests that a certificate for such Warrant
Shares be registered in the name of ___________________ whose address is
_______________ and that such certificate be delivered to __________________
whose address is ________________. If said number of Warrant Shares is less
than all of the Warrant Shares obtainable hereunder, the undersigned requests
that a new Warrant Certificate representing the remaining balance of the
Warrant Shares be registered in the name of _________________ whose address is
_________________ and that such Warrant Certificate be delivered to
__________________ whose address is_______________________.



Signature:



__________________________________________
(Signature must conform in all respects to name of holder as specified on the
face of the Warrant Certificate.)


Date:_____________


*    Consisting of:

          _____ shares of Common Stock

          _____ shares of Convertible Preferred Stock

                                    A-1-5
<PAGE>
 
                                                                     EXHIBIT A-2

                      FORM OF SERIES B WARRANT CERTIFICATE

THE WARRANTS AND SHARES REPRESENTED BY THIS SERIES B WARRANT CERTIFICATE HAVE
NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY
APPLICABLE STATE SECURITIES LAW AND MAY NOT BE SOLD OR TRANSFERRED IN THE
ABSENCE OF SUCH REGISTRATION OR AN EXEMPTION THEREFROM UNDER SUCH ACT OR LAW.
SUCH WARRANTS AND SHARES MAY BE TRANSFERRED ONLY IN COMPLIANCE WITH THE
CONDITIONS SPECIFIED IN AND ARE SUBJECT TO OTHER PROVISIONS OF THE WARRANT
AGREEMENT, DATED AS OF JULY 12, 1995, (AS AMENDED) BETWEEN THE ISSUER AND
CREDITANSTALT CORPORATE FINANCE, INC., A COMPLETE AND CORRECT COPY OF WHICH IS
AVAILABLE FOR INSPECTION AT THE PRINCIPAL OFFICE OF THE ISSUER AND WILL BE
FURNISHED TO THE HOLDER HEREOF UPON WRITTEN REQUEST AND WITHOUT CHARGE.

THE WARRANTS REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN MANDATORY
REDEMPTION AND EXCHANGE RIGHTS MORE FULLY SET FORTH IN THE WARRANT AGREEMENT.

                                                            Certificate No. B-__
                                                                          [Date]


                         EXERCISABLE ONLY ON OR BEFORE
                               November 15, 2006

                          Series B Warrant Certificate

     This Series B Warrant Certificate (this "Warrant Certificate") certifies
that Creditanstalt-Bankverein ("Creditanstalt"), or registered assigns, is the
registered holder of 205,000 Warrants (the "Warrants") to purchase Common
Stock or Convertible Preferred Stock of Uncle B's Bakery, Inc., an Iowa
corporation (the "Issuer"). Each Warrant entitles the holder, but only subject
to the conditions set forth herein and in the Warrant Agreement referred to
below, to purchase from the Issuer before 5:00 P.M., New York time, on
November 15, 2006 (the "Expiration Date"), one (1) fully paid and
nonassessable share of the Common Stock or Convertible Preferred Stock of the
Issuer (the "Warrant Shares") in the percentages and to the extent set forth
in the Warrant Agreement, at a price (the "Exercise Price") of $0.55 per
Warrant payable in lawful money of the United States of America, upon
surrender of this Warrant Certificate, execution of the annexed Form of
Election to Purchase and payment of the Exercise Price at the office of the
Issuer at 441 Dubuque Street, Ellsworth, Iowa 50075, or such other address as
the Issuer may specify in writing to the registered holder of Warrants
evidenced hereby (the "Warrant Office"). In lieu of exercising Warrants
pursuant to the immediately preceding sentence, the Warrant holder shall have
the right to require the Issuer to convert the

                                    A-2-1
<PAGE>
 
Warrants, in whole or in part and at any time or times, into Warrant Shares,
by surrendering to the Issuer the Warrant Certificate evidencing the Warrants
to be converted, accompanied by the annexed Form of Notice of Conversion which
has been duly completed and signed. The Exercise Price and number of Warrant
Shares purchasable upon exercise of the Warrants are subject to adjustment
prior to the Expiration Date as set forth in the Warrant Agreement. In no
event shall this Warrant be exercisable for shares of Common Stock or
Convertible Preferred Stock which, when aggregated with all other capital
stock of the Issuer (other than shares of Non-Attributable Stock) then held or
previously held by or currently issuable without restriction to Creditanstalt
or its Affiliates would, upon issuance, represent in excess of 24.99% of the
Equity of the Issuer (defined in the Warrant Agreement) unless such shares,
when issued, would constitute Non-Attributable Stock (as defined in the
Warrant Agreement).

     No Warrant may be exercised after 5:00 P.M., New York time, on the
Expiration Date and (except as otherwise provided in the Warrant Agreement)
all rights of the registered holders of the Warrants shall cease after 5:00
P.M., New York time, on the Expiration Date.

     The Issuer may deem and treat the registered holders of the Warrants
evidenced hereby as the absolute owners thereof (notwithstanding any notation
of ownership or other writing hereon made by anyone), for the purpose of any
exercise hereof and of any distribution to the holders hereof and for all
other purposes, and the Issuer shall not be affected by any notice to the
contrary.

     Warrant Certificates, when surrendered at the office of the Issuer at the
Warrant Office by the registered holder hereof in person or by a legal
representative duly authorized in writing, may be exchanged, in the manner and
subject to the limitations provided in the Warrant Agreement, but without
payment of any service charge, for another Warrant Certificate or Warrant
Certificates of like tenor evidencing in the aggregate a like number of
Warrants.

     Upon due presentment for registration of transfer of this Warrant
Certificate at the Warrant Office, a new Warrant Certificate or Warrant
Certificates of like tenor and evidencing in the aggregate a like number of
Warrants shall be issued in exchange for this Warrant Certificate to the
transferee(s) and, if less than all the Warrants evidenced hereby are to be
transferred, to the registered holder hereof, subject to the limitations
provided in the Warrant Agreement, without charge except for any tax or other
governmental charge imposed in connection therewith.

     This Warrant Certificate is one of the Warrant Certificates referred to
in the Warrant Agreement, dated as of July 12, 1995, (as amended) between the
Issuer and Creditanstalt Corporate Finance, Inc.. Said Warrant Agreement is
hereby incorporated by reference in and made a part of this instrument and is
hereby referred to for a description of the rights, limitation of rights,
obligations, duties and immunities thereunder of the Issuer and the holders.

                                    A-2-2
<PAGE>
 
  IN WITNESS WHEREOF the Issuer has caused this Warrant Certificate to be signed
by its duly authorized officers and has caused its corporate seal to be affixed
hereunto.


ATTEST:                             UNCLE B'S BAKERY, INC.

__________________________          By:___________________________

________________, Secretary           ________________, President


[Corporate Seal]


                                    A-2-3
<PAGE>
 
                                                          ANNEX to Form
                                                          of Series B Warrant
                                                          Certificate

                          FORM OF ELECTION TO PURCHASE

                   (To be executed upon exercise of Warrant)
                                        
     The undersigned hereby irrevocably elects to exercise the right,
represented by this Warrant Certificate, to purchase _______________ Warrant
Shares* and herewith tenders payment for such Warrant Shares to the order of
the Issuer in the amount of $_____________ in accordance with the terms
hereof. The undersigned requests that a certificate for such Warrant Shares be
registered in the name of _____________ whose address is ______________ and
that such certificate be delivered to whose address is ____________________.
If said number of Warrant Shares is less than all of the Warrant Shares
purchasable hereunder, the undersigned requests that a new Warrant Certificate
representing the remaining balance of the Warrant Shares be registered in the
name of __________________ whose address is ______________ and that such
Warrant Certificate be delivered to _________________ whose address is 
_______________________.


Signature:


__________________________________________
(Signature must conform in all respects to name of holder as specified on the
face of the Warrant Certificate.)


Date:_____________


*    Consisting of:

          _____ shares of Common Stock

          _____ shares of Convertible Preferred Stock


                                    A-2-4
<PAGE>
 
                                                  ANNEX to Form
                                                  of Series B Warrant
                                                  Certificate

                          FORM OF NOTICE OF CONVERSION

                  (To be executed upon conversion of Warrant)

     The undersigned hereby irrevocably elects to exercise the right,
represented by this Warrant Certificate, to convert Warrants represented
hereby into ______________________ Warrant Shares* in accordance with the
terms hereof. The undersigned requests that a certificate for such Warrant
Shares be registered in the name of ___________________ whose address is
__________________ and that such certificate be delivered to ________________
whose address is ____________________. If said number of Warrant Shares is
less than all of the Warrant Shares obtainable hereunder, the undersigned
requests that a new Warrant Certificate representing the remaining balance of
the Warrant Shares be registered in the name of _______________ whose address
is and that such Warrant Certificate be delivered to _______________ whose
address is ___________________.


Signature:


__________________________________________
(Signature must conform in all respects to name of holder as specified on the
face of the Warrant Certificate.)


Date:_____________


  *    Consisting of:

          _____ shares of Common Stock

          _____ shares of Convertible Preferred Stock


                                    A-2-5
<PAGE>
 
                                                                     EXHIBIT A-3

                      FORM OF SERIES C WARRANT CERTIFICATE

THE WARRANTS AND SHARES REPRESENTED BY THIS SERIES C WARRANT CERTIFICATE HAVE
NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY
APPLICABLE STATE SECURITIES LAW AND MAY NOT BE SOLD OR TRANSFERRED IN THE
ABSENCE OF SUCH REGISTRATION OR AN EXEMPTION THEREFROM UNDER SUCH ACT OR LAW.
SUCH WARRANTS AND SHARES MAY BE TRANSFERRED ONLY IN COMPLIANCE WITH THE
CONDITIONS SPECIFIED IN AND ARE SUBJECT TO OTHER PROVISIONS OF THE WARRANT
AGREEMENT, DATED AS OF JULY 12, 1995, (AS AMENDED) BETWEEN THE ISSUER AND
CREDITANSTALT CORPORATE FINANCE, INC., A COMPLETE AND CORRECT COPY OF WHICH IS
AVAILABLE FOR INSPECTION AT THE PRINCIPAL OFFICE OF THE ISSUER AND WILL BE
FURNISHED TO THE HOLDER HEREOF UPON WRITTEN REQUEST AND WITHOUT CHARGE.

THE WARRANTS REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN MANDATORY
REDEMPTION AND EXCHANGE RIGHTS MORE FULLY SET FORTH IN THE WARRANT AGREEMENT.

                                                            Certificate No. C-__
                                                                          [Date]


                         EXERCISABLE ONLY ON OR BEFORE
                                August 22, 2007

                          Series C Warrant Certificate

     This Series C Warrant Certificate (this "Warrant Certificate") certifies
that Creditanstalt-Bankverein ("Creditanstalt"), or registered assigns, is the
registered holder of 650,000 Warrants (the "Warrants") to purchase Common
Stock or Convertible Preferred Stock of Uncle B's Bakery, Inc., an Iowa
corporation (the "Issuer"). Each Warrant entitles the holder, but only subject
to the conditions set forth herein and in the Warrant Agreement referred to
below, to purchase from the Issuer before 5:00 P.M., New York time, on August
22, 2007 (the "Expiration Date"), one (1) fully paid and nonassessable share
of the Common Stock or Convertible Preferred Stock of the Issuer (the "Warrant
Shares") in the percentages and to the extent set forth in the Warrant
Agreement, at a price (the "Exercise Price") of $0.55 per Warrant payable in
lawful money of the United States of America, upon surrender of this Warrant
Certificate, execution of the annexed Form of Election to Purchase and payment
of the Exercise Price at the office of the Issuer at 441 Dubuque Street,
Ellsworth, Iowa 50075, or such other address as the Issuer may specify in
writing to the registered holder of Warrants evidenced hereby (the "Warrant
Office"). In lieu of exercising Warrants pursuant to the immediately preceding
sentence, the Warrant holder shall have the right to require the Issuer to
convert the Warrants, in whole or in part and at

                                    A-3-1
<PAGE>
 
any time or times, into Warrant Shares, by surrendering to the Issuer the
Warrant Certificate evidencing the Warrants to be converted, accompanied by
the annexed Form of Notice of Conversion which has been duly completed and
signed. The Exercise Price and number of Warrant Shares purchasable upon
exercise of the Warrants are subject to adjustment prior to the Expiration
Date as set forth in the Warrant Agreement. In no event shall this Warrant be
exercisable for shares of Common Stock or Convertible Preferred Stock which,
when aggregated with all other capital stock of the Issuer (other than shares
of Non-Attributable Stock) then held or previously held by or currently
issuable without restriction to Creditanstalt or its Affiliates would, upon
issuance, represent in excess of 24.99% of the Equity of the Issuer (defined
in the Warrant Agreement) unless such shares, when issued, would constitute
Non-Attributable Stock (as defined in the Warrant Agreement).

     No Warrant may be exercised after 5:00 P.M., New York time, on the
Expiration Date and (except as otherwise provided in the Warrant Agreement)
all rights of the registered holders of the Warrants shall cease after 5:00
P.M., New York time, on the Expiration Date.

     The Issuer may deem and treat the registered holders of the Warrants
evidenced hereby as the absolute owners thereof (notwithstanding any notation
of ownership or other writing hereon made by anyone), for the purpose of any
exercise hereof and of any distribution to the holders hereof and for all
other purposes, and the Issuer shall not be affected by any notice to the
contrary.

     Warrant Certificates, when surrendered at the office of the Issuer at the
Warrant Office by the registered holder hereof in person or by a legal
representative duly authorized in writing, may be exchanged, in the manner and
subject to the limitations provided in the Warrant Agreement, but without
payment of any service charge, for another Warrant Certificate or Warrant
Certificates of like tenor evidencing in the aggregate a like number of
Warrants.

     Upon due presentment for registration of transfer of this Warrant
Certificate at the Warrant Office, a new Warrant Certificate or Warrant
Certificates of like tenor and evidencing in the aggregate a like number of
Warrants shall be issued in exchange for this Warrant Certificate to the
transferee(s) and, if less than all the Warrants evidenced hereby are to be
transferred, to the registered holder hereof, subject to the limitations
provided in the Warrant Agreement, without charge except for any tax or other
governmental charge imposed in connection therewith.

     This Warrant Certificate is one of the Warrant Certificates referred to
in the Warrant Agreement, dated as of July 12, 1995, (as amended) between the
Issuer and Creditanstalt Corporate Finance, Inc.. Said Warrant Agreement is
hereby incorporated by reference in and made a part of this instrument and is
hereby referred to for a description of the rights, limitation of rights,
obligations, duties and immunities thereunder of the Issuer and the holders.

                                    A-3-2
<PAGE>
 
     IN WITNESS WHEREOF the Issuer has caused this Warrant Certificate to be
signed by its duly authorized officers and has caused its corporate seal to be
affixed hereunto.


ATTEST:                             UNCLE B'S BAKERY, INC.

__________________________          By:__________________________

________________, Secretary           ________________, President


[Corporate Seal]


                                    A-3-3
<PAGE>
 
                                                  ANNEX to Form
                                                  of Series C Warrant
                                                  Certificate

                          FORM OF ELECTION TO PURCHASE

                   (To be executed upon exercise of Warrant)

     The undersigned hereby irrevocably elects to exercise the right,
represented by this Warrant Certificate, to purchase ________________ Warrant
Shares* and herewith tenders payment for such Warrant Shares to the order of
the Issuer in the amount of $______________ in accordance with the terms
hereof. The undersigned requests that a certificate for such Warrant Shares be
registered in the name of _______________________ whose address is
________________ and that such certificate be delivered to whose address is
___________________. If said number of Warrant Shares is less than all of the
Warrant Shares purchasable hereunder, the undersigned requests that a new
Warrant Certificate representing the remaining balance of the Warrant Shares
be registered in the name of __________________ whose address is
_______________________ and that such Warrant Certificate be delivered to
___________________ whose address is _________________________.


Signature:


__________________________________________
(Signature must conform in all respects to name of holder as specified on the
face of the Warrant Certificate.)


Date:_____________


*    Consisting of:

          _____ shares of Common Stock
        
          _____ shares of Convertible Preferred Stock


                                    A-3-4
<PAGE>
 
                                                  ANNEX to Form
                                                  of Series C Warrant
                                                  Certificate

                          FORM OF NOTICE OF CONVERSION

                  (To be executed upon conversion of Warrant)

     The undersigned hereby irrevocably elects to exercise the right,
represented by this Warrant Certificate, to convert Warrants represented
hereby into ______________________ Warrant Shares* in accordance with the
terms hereof. The undersigned requests that a certificate for such Warrant
Shares be registered in the name of ___________________ whose address is
__________________ and that such certificate be delivered to
__________________ whose address is ___________________. If said number of
Warrant Shares is less than all of the Warrant Shares obtainable hereunder,
the undersigned requests that a new Warrant Certificate representing the
remaining balance of the Warrant Shares be registered in the name of
___________________ whose address is ________________________ and that such
Warrant Certificate be delivered to ________________ whose address
is__________________.


Signature:


__________________________________________
(Signature must conform in all respects to name of holder as specified on the
face of the Warrant Certificate.)


Date:_____________


*    Consisting of:

          _____ shares of Common Stock

          _____ shares of Convertible Preferred Stock


                                    A-3-5
<PAGE>
 
                                   SCHEDULE I

      OUTSTANDING OPTIONS, WARRANTS, SUBSCRIPTIONS, RIGHTS, CONVERTIBLE OR
 EXCHANGEABLE SECURITIES OR OTHER AGREEMENTS OF PLANS UNDER WHICH ISSUER MAY BE
OR BECOME OBLIGATED TO ISSUE, SELL OR TRANSFER SHARES OF CAPITAL STOCK OR OTHER
                                   SECURITIES
                                        
<PAGE>
 
                                  SCHEDULE II

                              REGISTRATION RIGHTS



1.   Employment Agreement dated July 23, 1993 by and between Uncle B's Bakery,
     Inc. (formerly known as It Works, Inc.) and William T. Rose, Jr.

2.   Employment Agreement dated July 23, 1993 by and between Uncle B's Bakery,
     Inc. (formerly known as It Works, Inc.) and William T. Rose, Sr.

3.   Warrant to purchase 160,030 shares of Common Stock of Uncle B's Bakery,
     Inc. issued to John G. Kinnard and Company, Incorporated pursuant to an
     Underwriting Agreement dated October 13, 1993.

4.   Warrant Agreement dated as of July 12, 1995 by and between Uncle B's
     Bakery, Inc. and Creditanstalt Corporate Finance, Inc., as amended by the
     First Amendment to Warrant Agreement and this Second Amendment to Warrant
     Agreement.