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                                                                    EXHIBIT 10.8

                      SECOND AMENDMENT TO CREDIT AGREEMENT

     This SECOND AMENDMENT TO CREDIT AGREEMENT (this "Amendment"), made and
entered into as of December 24, 1999, is by and between BUCA, INC., a Minnesota
corporation (the "Borrower"), the banks which are signatories hereto
(individually, a "Bank" and, collectively, the "Banks"), BANK OF AMERICA, N.A.,
a national banking association ("B of A"), as one of the Banks and as co-agent
for the Banks (in such capacity, a "Co-Agent"), BANKBOSTON, N.A., a national
banking association, as one of the Banks and as co-agent for the Banks (in such
capacity, a "Co-Agent") and U.S. BANK NATIONAL ASSOCIATION, a national banking
association, as one of the Banks, and as agent for the Banks (in such capacity,
the "Agent").

                                    RECITALS
                                    --------

     1. U.S. Bank National Association, as Agent and as a Bank, and Bank of
America, N.A., as Co-Agent and as a Bank, and the Borrower entered into a Credit
Agreement dated as of September 27, 1999, as amended by that First Amendment to
Credit Agreement dated as of October 21, 1999 among U.S. Bank National
Association, as Agent and as a Bank, Bank of America, N.A., as Co-Agent and as a
Bank, and BankBoston, N.A., as Co-Agent and a Bank (the "Credit Agreement"); and

     2. The Borrower has requested that the Banks amend the Credit Agreement in
certain respects.

     3. The parties desire to amend the Credit Agreement, subject to the terms
and conditions set forth in this Amendment.

                                    AGREEMENT
                                    ---------

     NOW, THEREFORE, for good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, the parties hereto hereby covenant
and agree to be bound as follows:

     Section 1. Capitalized Terms. Capitalized terms used herein and not
otherwise defined herein shall have the meanings assigned to them in the Credit
Agreement, unless the context shall otherwise require.

     Section 2. Amendment. The Credit Agreement is hereby amended as follows:

          2.1 Definitions
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               (a) The following new definitions of "Equity Interests" and
          "Pledge Agreement (Subsidiary)" are hereby added to the Credit
          Agreement in the correct alphabetical order thereto, and the form of
          Pledge Agreement (Subsidiary) attached hereto is hereby made part of
          the Credit Agreement as Exhibit 1.1-2A thereto:

                    "Equity Interests": Ownership or equity interests
                    (including, without limitation, an interest in the profits
                    of any entity) in any corporation, limited liability
                    company, association, partnership (whether general or
                    limited), limited liability partnership, joint venture,
                    trust, or business trust.

                    "Pledge Agreement (Subsidiary)": A pledge agreement in the
                    form of Exhibit 1.1-2A hereto.

               (b) The definitions of "Affiliate", "Partially Owned
          Subsidiaries", "Restricted Payments", "Subsidiary", and "Wholly-owned
          Subsidiary" are hereby amended in their entireties to read as follows:

               "Affiliate": When used with reference to any Person, (a) each
               Person that, directly or indirectly, controls, is controlled by
               or is under common control with, the Person referred to, (b) each
               Person which beneficially owns or holds, directly or indirectly,
               five percent or more of any class of voting Equity Interests of
               the Person referred to, (c) each Person, five percent or more of
               the voting Equity Interest of which is beneficially owned or
               held, directly or indirectly, by the Person referred to, and (d)
               each of such Person's officers, directors, joint venturers,
               governors and partners (both general and limited). The term
               control (including the terms "controlled by" and "under common
               control with") means the possession, directly, of the power to
               direct or cause the direction of the management and policies of
               the Person in question.

               "Partially-Owned Subsidiaries": Subsidiaries in which the
               Borrower, directly or through its Subsidiaries, owns less than
               100% of the securities or other Equity Interests having ordinary
               voting power for the election of the board of directors or other
               Persons performing similar functions (other than qualifying
               shares or other Equity Interests held by directors or other
               Persons performing similar functions) or, in the case of a
               partnership, less than a 100% interest in the profits or capital
               thereof.

               "Restricted Payments": With respect to the Borrower and the
               Partially-Owned Subsidiaries, collectively, all dividends or
               other distributions of any nature (whether in cash, securities or
               Equity Interests of the Borrower or the Partially-Owned
               Subsidiaries, assets or otherwise) on or in respect of, and all
               payments on, any class of Equity Interests (including warrants,
               options or rights therefor, but excluding Indebtedness which is
               convertible into any Equity Interest, including without
               limitation

                                      -2-
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               common or preferred stock, which is itself not convertible into
               Indebtedness) issued by the Borrower or any of the
               Partially-Owned Subsidiaries, whether such Equity Interests are
               authorized or outstanding on the Closing Date or at any time
               thereafter, and any redemption or purchase of, or distribution in
               respect of, any of the foregoing, whether directly or indirectly,
               including any Equity Interest of the Borrower or any or the
               Partially-Owned Subsidiaries.

               "Subsidiary": Any corporation or other entity of which Equity
               Interests having ordinary voting power for the election of a
               majority of the board of directors or other Persons performing
               similar functions are owned by the Borrower either directly or
               through one or more Subsidiaries, and any partnership if more
               than a 50% interest in the profits or capital thereof is owned by
               the Borrower either directly or though one or more Subsidiaries
               (unless such partnership can and does ordinarily take major
               business actions without the prior approval of the Borrower or
               one or more Subsidiaries).

               "Wholly Owned Subsidiaries": Subsidiaries which are not
               Partially-Owned Subsidiaries.

          2.2 Organization, Standing, Etc. Section 4.1 of the Credit Agreement
     is hereby amended (i) by restating the second sentence thereof in its
     entirety to read as follows:

          Each Subsidiary is a corporation, limited partnership or limited
          liability company duly formed and validly existing and in good
          standing under the laws of the jurisdiction of its organization and
          has all requisite corporate, limited partnership or limited liability
          company power and authority to carry on its business as now conducted.

          and (ii) by deleting the phrase "foreign corporation" and replacing it
          with "foreign corporation, limited partnership or limited liability
          company".

          2.3 Capitalization of the Borrower and Subsidiaries: Subsection (b)
     and the following paragraph thereof in Section 4.21 of the Credit Agreement
     are hereby amended in their entireties to read as follows:

          (b) a list of all Subsidiaries of the Borrower and, as applicable, the
          number and percentage of the authorized, issued and outstanding Equity
          Interests owned beneficially or of record by the Borrower or any such
          Subsidiary therein, and the jurisdiction or organization of that
          Subsidiary.

          As of the Closing Date, all of the outstanding capital stock of the
     Borrower will be validly issued, fully paid and nonassessable, and all of
     the outstanding Equity Interests of the Subsidiaries will be validly
     issued, fully paid and nonassessable, and will be owned beneficially

                                      -3-
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     and of record directly as set forth on Schedule 4.21, subject to no Liens
     other than Liens in favor of the Agent, for itself and the benefit of the
     Banks, and the restrictions set forth in Schedule 4.21. Except as reflected
     on Schedule 4.21, as of the Closing Date, none of the Subsidiaries has
     outstanding any capital stock appreciation or phantom capital stock rights
     or plans or other similar rights with respect to its Equity Interests, or
     is subject to any obligation (contingent or otherwise) to repurchase or
     otherwise acquire or retire any of its Equity Interests. Except as set
     forth on Schedule 4.21, there are no statutory or contractual preemptive
     rights or rights of first offer or refusal with respect to the Equity
     Interests of any of the Subsidiaries. Neither the Borrower nor any of the
     Subsidiaries has violated any applicable securities laws in connection with
     the offer, sale or issuance of any of its respective Equity Interests.

          2.4 Corporate Existence. Section 5.2 of the Credit Agreement is hereby
     amended by deleting the word "corporation" where it appears therein and
     replacing it with the phrase "corporation, limited partnership or limited
     liability company".

          2.5 New Restaurants. Section 5.19 of the Credit Agreement is hereby
     amended in its entirety to read as follows:

          Section 5.19 New Restaurants. The Borrower agrees that each new
          Restaurant created or acquired from and after the Closing Date shall
          be owned or leased and operated only by a Wholly-Owned Subsidiary, the
          Equity Interests which Equity Interests shall be certificated) of
          which have been pledged and delivered to the Agent pursuant to the
          Pledge Agreement or the Pledge Agreement (Subsidiary), as applicable.

          2.6 Subsidiaries. Section 6.5 of the Credit Agreement is hereby
     amended to read in its entirety as follows:

          Section 6.5 Subsidiaries. After the date of this Agreement, the
          Borrower will not, and will not permit any Subsidiary to, form or
          acquire any Person which would thereby become a Subsidiary, except
          that, the Borrower or any Subsidiary may form a corporation, limited
          liability company, or limited partnership ("New Entity") that would
          thereby become a Wholly-Owned Subsidiary provided such Borrower or
          Subsidiary provides 30 days' prior written notice to the Agent of any
          capitalization of such New Entity in excess of any deminimus
          capitalization necessary for the organization of such New Entity. In
          the event the Borrower hereafter forms a New Entity that thereby
          becomes a Wholly-Owned Subsidiary, then upon such formation such New
          Entity shall promptly: (a) certificate all Equity Interests in such
          New Entity in form and substance reasonably satisfactory to the Agent
          and its counsel; and (b) deliver a Guaranty, a Security Agreement
          (Guarantor) and related UCC financing statements for filing in such

                                      -4-
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          jurisdictions as the Agent shall request, all duly executed by such
          New Entity, and the Borrower shall deliver to the Agent (x) in the
          case of a New Entity owned directly by the Borrower, an amendment to
          the Pledge Agreement in respect of such New Entity in form and
          substance reasonably satisfactory to the Agent; and (y) in the case of
          a New Entity owned by a Subsidiary, a Pledge Agreement (Subsidiary) in
          respect of such New Entity, in each case duly executed by the Borrower
          or the applicable Subsidiary, and the certificates representing the
          Borrower's or the applicable Subsidiary's ownership of 100% of the
          Equity Interests of such New Entity, together with stock powers or
          other comparable assignment forms related thereto requested by the
          Agent.

          2.7 Capital Expenditures. Section 6.10 of the Credit Agreement is
     hereby amended to read in its entirety as follows:

          Section 6.10 Capital Expenditures. The Borrower will not, and will not
          permit any Subsidiary to, make Capital Expenditures in an amount
          exceeding, on a consolidated basis, $31,000,000 during Fiscal Year
          1999 and $22,000,000 during any Fiscal Year thereafter; provided that
          all Capital Expenditures shall be invested in the development of new
          Restaurants or the maintenance of existing Restaurants or in the
          construction, acquisition, repair or maintenance of the Borrower's
          corporate headquarters.

          2.8 Investments. Section 6.12(h) of the Agreement is hereby amended to
     read in its entirety as follows:

          6.12(h) Equity Interests in any Subsidiary, the formation or
          acquisition of which is permitted under Section 6.5.

          2.9 Modification of Ownership or Equity Structure. Section 6.23 of the
     Credit Agreement is hereby amended to read in its entirety as follows:

          Section 6.23 Modification of Ownership or Equity Structure. The
          Borrower will not permit any Subsidiary to issue or authorize the
          issuance of Equity Interests of such Subsidiary (other than qualifying
          shares or other Equity Interest held by directors or other Persons
          performing similar functions) which would result in any other Person
          becoming an owner thereof; issue or authorize the issuance of options
          to purchase Equity Interests of such Subsidiary which immediately, or
          in the future upon the exercise of rights granted therein, would
          result in any other Person becoming an owner thereof; issue or
          authorize the issuance of warrants to purchase Equity Interests of
          such Subsidiary which immediately, or in the future upon the exercise
          of rights granted therein, would result in any other Person becoming
          an owner thereof; issue or authorize the issuance of securities or
          instruments convertible into Equity Interests of such Subsidiary which
          immediately, or in the future upon the exercise of rights granted

                                      -5-
<PAGE>

          therein, would result in any other Person becoming an owner thereof;
          or authorize, issue or grant any stock appreciation rights, phantom
          stock, profit participations or other similar rights with respect to
          the Equity Interests of such Subsidiary which immediately, or in the
          future upon the exercise of rights granted therein, would result in
          any other Person becoming an owner thereof.

     Section 3. Effectiveness of Amendments. The amendments contained in this
Amendment shall become effective upon delivery by the Borrower of, and
compliance by the Borrower with, the following:

          3.1 This Amendment, duly executed by the Borrower.

          3.2 A certificate of the Secretary or Assistant Secretary of the
     Borrower (a) certifying as to a copy of the resolutions of the Board of
     Directors of the Borrower authorizing the execution, delivery and
     performance of this Amendment, (b) certifying that there has been no
     amendment to the Articles of Incorporation or Bylaws of the Borrower since
     true and accurate copies of the same were delivered to the Agent with a
     certificate of the Secretary of the Borrower dated September 27, 1999, and
     (c) certifying as to the name, title, and specimen signature of the officer
     or officers of the Borrower authorized to execute this Amendment, and any
     other instrument or agreement executed by the Borrower in connection with
     this Amendment.

          3.3 Payment of all reasonable unpaid legal fees and other
     out-of-pocket expenses incurred by the Agent through the date of this
     Amendment in connection with this Amendment of which the Borrower has been
     notified as of the date of this Amendment.

     Section 4. Representations, Warranties, Authority, No Adverse Claim.

          4.1 Reassertion of Representations and Warranties, No Default. The
     Borrower hereby represents that on and as of the date hereof and after
     giving effect to this Amendment (a) all of the representations and
     warranties contained in the Credit Agreement are true and correct in all
     respects as of the date hereof as though made on and as of such date,
     except for changes permitted by the terms of the Credit Agreement, and (b)
     there will exist no Default or Event of Default under the Credit Agreement
     as amended by this Amendment on such date which has not been waived by the
     Agent.

          4.2 Authority, No Conflict, No Consent Required. The Borrower
     represents and warrants that the Borrower has the corporate power and
     authority to enter into this Amendment and has duly authorized the
     execution and delivery of this Amendment and any other agreements and
     documents executed and delivered by the Borrower in connection herewith by
     proper corporate action, and, except as set forth in Schedule 4.3 to the
     Credit Agreement, none of this Amendment nor

                                      -6-
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     the agreements contained herein contravenes or constitutes a default under
     any agreement, instrument or indenture to which the Borrower is a party or
     a signatory or a provision of the Borrower's Articles of Incorporation,
     Bylaws or any requirement of law presently in effect and applicable to the
     Borrower, or results in the imposition of any Lien on any of its property
     under any agreement binding on or applicable to the Borrower or any of its
     property except, if any, in favor of the Agent and except where the
     contravention or default or the imposition of such Lien could not adversely
     affect the validity or enforceability of this Amendment or constitute a
     Material Adverse Occurrence. The Borrower represents and warrants that,
     except as set forth in Schedule 4.3 to the Credit Agreement, no consent,
     approval or authorization of or registration or declaration with any
     Person, including but not limited to any governmental authority, is
     required on the part of the Borrower in connection with the execution and
     delivery by the Borrower of this Amendment or any other agreements and
     documents executed and delivered by the Borrower in connection herewith or
     the performance of obligations of the Borrower herein described, except for
     those which the Borrower has obtained or provided and as to which the
     Borrower has delivered certified copies of documents evidencing each such
     action to the Agent and except where the failure to obtain such consent,
     approval or authorization or to make such registration or declaration could
     not adversely effect the validity or enforceability of this Amendment or
     constitute a Material Adverse Occurrence.

          4.3 No Adverse Claim. The Borrower warrants, acknowledges and agrees
     that to the Borrower's knowledge no events have been taken place and no
     circumstances exist at the date hereof which would give the Borrower a
     basis to assert a defense, offset or counterclaim to any claim of the Banks
     with respect to the Borrower's obligations under the Credit Agreement as
     amended by this Amendment.

     Section 5. Affirmation of Credit Agreement, Further References, Affirmation
of Security Interest. The Banks and the Borrower each acknowledge and affirm
that the Credit Agreement, as hereby amended, is hereby ratified and confirmed
in all respects and all terms, conditions and provisions of the Credit
Agreement, except as amended by this Amendment, shall remain unmodified and in
full force and effect. All references in any document or instrument to the
Credit Agreement are hereby amended and shall refer to the Credit Agreement as
amended by this Amendment. The Borrower confirms to the Banks that the
Borrower's obligations under the Credit Agreement, as amended by this Amendment,
are and continue to be secured by the security interest granted by the Borrower
in favor of the Agent under that certain Security Agreement (Borrower), that
certain Pledge Agreement, and that certain Collateral Assignment of Trademarks,
all dated as of September 27, 1999, and made by the Borrower in favor of the
Agent, and all of the terms, conditions, provisions, agreements, requirements,
promises, obligations, duties, covenants and representations of the Borrower
under such documents and any and all other documents and agreements entered into
with respect to the obligations under the Credit Agreement are incorporated
herein by reference and are hereby ratified and affirmed in all respects by the
Borrower.

                                      -7-
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     Section 6. Successors. This Amendment shall be binding upon the Borrower
and the Banks and their respective successors and assigns, and shall inure to
the benefit of the Borrower and the Banks and the successors and assigns of the
Banks.

     Section 7. Legal Expenses. As provided in Section 9.2 of the Credit
Agreement, the Borrower agrees to reimburse the Agent, upon execution of this
Amendment, for all reasonable out-of-pocket expenses (including reasonable
attorney' fees and legal expenses of Dorsey & Whitney LLP, counsel for the
Agent) incurred in connection with negotiation, preparation and execution of
this Amendment and all other documents negotiated, prepared and executed in
connection with this Amendment, and in enforcing the obligations of the Borrower
under this Amendment, and to pay and save the Banks harmless from all liability
for any stamp or other taxes which may be payable with respect to the execution
or delivery of this Amendment, which obligations of the Borrower shall survive
any termination of the Credit Agreement.

     Section 8. Counterparts. This Amendment may be executed in several
counterparts as deemed necessary or convenient, each of which, when so executed,
shall be deemed an original, provided that all such counterparts shall be
regarded as one and the same document, and any party to this Amendment may
execute such agreement by executing a counterpart of such agreement.

     Section 9. Governing Law. THIS AMENDMENT SHALL BE GOVERNED BY THE INTERNAL
LAWS OF THE STATE OF MINNESOTA, WITHOUT GIVING EFFECT TO CONFLICT OF LAW
PRINCIPLES THEREOF, BUT GIVING EFFECT TO FEDERAL LAWS APPLICABLE TO NATIONAL
BANKS, THEIR HOLDING COMPANIES AND THEIR AFFILIATES.

                                      -8-
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     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed as of the date and year first above written.

BORROWER:                              BUCA, INC.


                                       By:    /s/ Greg Gadel
                                              --------------------------------
                                       Title: Chief Financial Officer
                                              --------------------------------

                                       Address:
                                       Attention: Greg A. Gadel
                                       1300 Nicollet Avenue
                                       Suite 5003
                                       Minneapolis, MN 55403

                                       Telephone No.:  (612) 288-2382
                                       Telecopier No.: (612) 827-6446


AGENT:                                 U.S. BANK NATIONAL ASSOCIATION

                                       By:    /s/ Joshua Pirozzolo
                                              --------------------------------
                                       Title: Commercial Banking Officer
                                              --------------------------------

                                       Address:
                                       Attention: Joshua R. Pirozzolo MPFP0602
                                       601 Second Avenue South
                                       Minneapolis, MN 55402-4302

                                       Telephone No.:  (612) 973-0520
                                       Telecopier No.: (612) 973-0823


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CO-AGENT:                              BANK OF AMERICA, N.A.

                                       By:    /s/ William Richards
                                              --------------------------------
                                       Title: Vice President
                                              --------------------------------

                                       Address:
                                       Attention: William S. Richards, Jr.
                                       IL1-231-06-13
                                       231 South LaSalle Street
                                       Chicago, IL 60697

                                       Telephone No.:  (312) 828-2731
                                       Telecopier No.: (312) 828-1974


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                       Signature Page to Second Amendment
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CO-AGENT:                              BANKBOSTON, N.A.

                                       By:    /s/ Christopher Holtz
                                              --------------------------------
                                       Title: Division Executive
                                              --------------------------------

                                       Address:
                                       Attention: Christopher M. Holtz
                                       MS 01-09-05
                                       100 Federal Street
                                       Boston, MA 02110

                                       Telephone No.:  (617) 434-7690
                                       Telecopier No.: (617) 434-0630


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