<PAGE>   1
                                                                    EXHIBIT 4.19

                                                                  EXECUTION COPY


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                        AMERICAN RESTAURANT GROUP, INC.

                                      AND

                             SUBSIDIARY GUARANTORS

                                      AND

                     U.S. TRUST COMPANY OF CALIFORNIA, N.A.
                                    Trustee




                           _________________________




                               FIRST SUPPLEMENTAL
                                   INDENTURE


                          Dated as of August 28, 1996





       =================================================================





<PAGE>   2

          FIRST SUPPLEMENTAL INDENTURE dated as of August 28, 1996 among
American Restaurant Group, Inc., a Delaware corporation (the "Company"), the
Subsidiary Guarantors and U.S. Trust Company of California, N.A., a national
banking association, as trustee (the "Trustee") under the Indenture dated as of
December 1, 1993 (the "Indenture").

                                    RECITALS

                 WHEREAS, pursuant to the Indenture, the Company issued
$50,000,000 aggregate principal amount of its 12% Senior Secured Notes due
September 15, 1998 (the "Securities");

                 WHEREAS, Section 9.02 of the Indenture provides, among other
things, that the Company, the Subsidiary Guarantors and the Trustee may, with
the consent of the holders of at least a majority in principal amount of the
then outstanding Securities (or, in the case of certain amendments, the consent
of each Securityholder affected), amend the Indenture and the Securities in
certain respects;

                 WHEREAS, the Company, pursuant to the foregoing authority,
proposes in and by this First Supplemental Indenture to amend the Indenture and
the Securities in certain respects; and

                 WHEREAS, all things necessary to make this First Supplemental
Indenture a valid agreement of the Company, the Subsidiary Guarantors and the
Trustee and a valid amendment of and supplement to the Indenture and the
Securities have been done.

                 NOW, THEREFORE, THIS FIRST SUPPLEMENTAL INDENTURE WITNESSETH:

                 For and in consideration of the premises, the Company, the
Subsidiary Guarantors and the Trustee agree as follows:


                                  ARTICLE ONE

                 AMENDMENTS TO THE INDENTURE AND THE SECURITIES

                 SECTION 1.01.  Amendment to Section 1.01--Consolidated EBITDA.
The definition of "Consolidated EBITDA" contained in Section 1.01 of the
Indenture is hereby amended by (a) adding the following new clauses (vii) and
(viii) after clause (vi) thereof:

                 ", (vii) in the case of calculations pursuant to Sections 4.04
                 and 4.26 only, rental expense attributable to Operating Leases
                 resulting from Sale/leasebacks (other than Specified
                 Sale/leaseback Transactions) consummated on or after the
                 Supplemental Indenture Effective Date, and (viii) in the case
                 of calculations pursuant to Sections 4.04 and 4.26 only, to
                 the extent Consolidated Net Income has been reduced thereby,
                 the amounts described in clause (v) of the definition of Net
                 Cash Proceeds"


<PAGE>   3
                                                                              2


and (b) adding the following clause (c) after clause (b) thereof:

                 "and (c) in the case of calculations pursuant to Sections 4.04
                 and 4.26 only, any portion of Consolidated EBITDA for such
                 period (determined without giving effect to this clause (c))
                 attributable to any operating unit, or any material portion of
                 the assets of an operating unit, of the Company and its
                 Subsidiaries as to which an EBITDA Adjustment Amount has been
                 established"

                 SECTION 1.02.  Amendment to Section 1.01--Net Cash Proceeds.
The definition of "Net Cash Proceeds" contained in Section 1.01 of the
Indenture is hereby amended by adding the following new clause (v) to the end
thereof:

                 "and (v) in the case of the Required Black Angus
                 Sale/leaseback Transaction, (1) consent fees paid by the
                 Company in connection with the First Supplemental Indenture or
                 in connection with the Second Supplemental Indenture with
                 respect to the Existing Note Indenture, (2) reasonable consent
                 fees, if any, paid to the Lenders in connection with
                 modifications to the Credit Agreement or to the holders of the
                 Subordinated Notes in connection with modifications to the
                 Subordinated Loan Agreement, in each case consummated
                 substantially concurrently with the Supplemental Indenture
                 Effective Date, and (3) without duplication of clause (i)
                 above, the reasonable fees and expenses of advisors and legal
                 counsel to the Company, the Trustee, the Holders, the Credit
                 Agent, the Lenders or the holders of the Subordinated Notes,
                 in each case to the extent reimbursed by the Company, in
                 connection with the transactions described in clauses (1) and
                 (2) above, all as certified in reasonable detail to the
                 Trustee by the Chief Financial Officer of the Company"

                 SECTION 1.03.  Amendment to Section 1.01--Net Proceeds Offer
Trigger Date.  The definition of "Net Proceeds Offer Trigger Date" contained in
Section 1.01 of the Indenture is hereby amended by (a) inserting the words "the
Reinvestment Net Cash Proceeds relating to" before the words "an Asset Sale"
contained in clause (b) thereof, (b) changing each reference to "Net Cash
Proceeds" or "gross proceeds" in clause (b) thereof to "Reinvestment Net Cash
Proceeds" and (c) adding a new clause (c) to the end thereof which shall read
in its entirety as follows:

                 "and (c) with respect to the Net Cash Proceeds (other than
                 Reinvestment Net Cash Proceeds) relating to an Asset Sale, the
                 date of receipt of such Net Cash Proceeds"

                 SECTION 1.04.  Amendment to Section 1.01--New Definitions.
Section 1.01 of the Indenture is hereby amended by adding the following
definitions in the appropriate alphabetical order:





<PAGE>   4
                                                                               3



                 "Aggregate EBITDA Adjustment Amount" means, at any date of
         determination, the aggregate of all EBITDA Adjustment Amounts (if any)
         determined with respect to Asset Sales consummated during the period
         from the Supplemental Indenture Effective Date to and including such
         date of determination.

                 "Consent Solicitation Statement" means the Consent
         Solicitation Statement of the Company dated August 2, 1996 relating to
         the First Supplemental Indenture.

                 "EBITDA Adjustment Amount" means, with respect to any Asset
         Sale (other than a Sale/leaseback) consummated on or after the
         Supplemental Indenture Effective Date involving an operating unit, or
         a material portion of the assets of an operating unit, of the Company
         and its Subsidiaries, that portion of Consolidated EBITDA attributable
         to such operating unit or material portion of the assets thereof for
         the most recent period of four consecutive fiscal quarters ending
         prior to the date of such Asset Sale for which the relevant financial
         information is available, as certified in reasonable detail to the
         Trustee by the Chief Financial Officer of the Company.

                 "First Supplemental Indenture" means the First Supplemental
         Indenture, dated as of August 28, 1996, with respect to this
         Indenture.

                 "Reinvestment Net Cash Proceeds" means, with respect to any
         Asset Sale, the maximum portion of the Net Cash Proceeds thereof that
         may be reinvested as provided in the first proviso contained in clause
         (A) of Section 4.17 (it being understood that all Net Cash Proceeds of
         a Specified Sale/leaseback Transaction shall constitute Reinvestment
         Net Cash Proceeds).

                 "Required Black Angus Sale/leaseback Transaction" means the
         Sale/leaseback described in Section 4.24 to the extent such
         transaction generates the minimum gross cash proceeds and minimum Net
         Cash Proceeds required thereby.

                 "Specified Sale/leaseback Transaction" means any
         Sale/leaseback with respect to all or any portion of the assets
         comprising a restaurant first opened by the Company or any of its
         Subsidiaries after the Supplemental Indenture Effective Date.

                 "Supplemental Indenture Effective Date" means the date on
         which the First Supplemental Indenture has become effective in
         accordance with its terms.

                 "13% Security" means any Security or portion thereof which
         bears interest at a stated per annum rate equal to 13% (representing
         the portion of the Securities (and any replacements therefor) as to
         which consents have been obtained pursuant to the Consent Solicitation
         Statement).

                 "12% Security" means any Security or portion thereof which
         bears interest at a stated per annum rate equal to 12% (representing
         the portion of the Securities (and any replacements therefor) as to
         which consents have not been obtained pursuant to





<PAGE>   5
                                                                               4



         the Consent Solicitation Statement).  It is understood that, effective
         on the Supplemental Indenture Effective Date, no 12% Securities shall
         be outstanding.

                 SECTION 1.05.  Amendment to Section 1.01--Deletion or
Amendment and Restatement of Certain Definitions.  Section 1.01 of the
Indenture is hereby amended by (a) deleting in their entirety the definitions
"Accelerated Payment", "Accelerated Payment Date", "Acceleration Date" and
"Offer" and (b) amending and restating in their entirety the following
definitions:

                 "Existing Notes" means the Company's 12% Senior Secured Notes
         issued pursuant to the Existing Note Indenture, as such notes may be
         amended, supplemented or otherwise modified from time to time.

                 "Existing Note Indenture" means the Note Indenture dated as of
         September 15, 1992 by and among the Company, the Subsidiary Guarantors
         and the Existing Notes Trustee, as such indenture may be amended,
         supplemented or otherwise modified from time to time.

                 SECTION 1.06.  Amendment to Section 3.07.  Section 3.07 of the
Indenture is hereby amended by (a) inserting the words "or concurrently
required to be applied or offered to be applied to purchase Existing Notes in
accordance with the Existing Note Indenture" after the words "the Letter of
Credit Obligations under the Credit Agreement" contained in clause (2) of
paragraph (a) thereof; (b) inserting at the end of the second proviso of
paragraph (a) thereof the parenthetical "(so long as such Net Cash Proceeds are
applied to prepay Working Capital Loans, secure Letter of Credit Obligations or
reduce the outstanding amount of letters of credit under the Credit
Agreement)"; (c) changing the amount "$5,000,000" contained in the third
proviso of paragraph (a) thereof to the amount "$2,000,000"; (d) deleting the
last sentence of paragraph (a) thereof; (e) replacing the words "not more than
10 days after" contained in paragraph (b) thereof with the word "on"; (f)
inserting after the word "tendered" contained in clause (7) of paragraph (b)
thereof the parenthetical "(or, in the case of 13% Securities, deemed
tendered)"; and (g) replacing the last paragraph of paragraph (b) thereof with
the following paragraphs:

                                  "Notwithstanding anything to the contrary in
                 this Section 3.07, with respect to each Net Proceeds Offer,
                 each Holder of 13% Securities shall, without any action on the
                 part of such Holder, (i) be deemed to have tendered on the
                 relevant Net Proceeds Offer Trigger Date the entire amount of
                 such Holder's 13% Securities in connection with such Net
                 Proceeds Offer and (ii) be entitled to redemption of a portion
                 of such Holder's 13% Securities on a pro rata basis determined
                 on the assumption that all Securities (including all 12%
                 Securities) have been tendered in connection with such Net
                 Proceeds Offer, with the Proceeds Purchase Date (a "13%
                 Securities Proceeds Purchase Date") associated with such
                 redemption being the Business Day immediately succeeding such
                 Net Proceeds Offer Trigger Date.  Unless the Company defaults
                 in making payment therefor in accordance with the next
                 succeeding





<PAGE>   6
                                                                               5



                 paragraph, the 13% Securities to be so redeemed shall cease to
                 accrue interest after the relevant 13% Securities Proceeds
                 Purchase Date.

                                  On or before a Proceeds Purchase Date
                 (including, in the case of 13% Securities, the applicable 13%
                 Securities Proceeds Purchase Date), the Company shall (i)
                 accept for payment Securities or portions thereof tendered
                 (or, in the case of 13% Securities, deemed tendered) pursuant
                 to the Net Proceeds Offer (with the amount so accepted being
                 calculated (x) in the case of 13% Securities, in the manner
                 specified in the preceding paragraph and (y) in the case of
                 12% Securities, on a pro rata basis if required pursuant to
                 paragraph (7) above) and (ii) by 10:00 a.m., New York City
                 time, deposit with the Paying Agent U.S. Legal Tender or
                 Securities acquired in the manner described in clause (a) of
                 this Section 3.07 sufficient to pay the purchase price of all
                 Securities or portions thereof so accepted or to be credited
                 against the Net Proceeds Offer.  Upon surrender of the
                 relevant Securities to the Paying Agent, the Paying Agent
                 shall promptly mail or deliver to Holders of Securities so
                 accepted payment in an amount equal to the purchase price, and
                 the Trustee shall promptly authenticate and mail or deliver to
                 such Holders new Securities equal in principal amount to any
                 unpurchased portion of the Securities surrendered.  Any
                 Securities not so accepted shall be promptly mailed or
                 delivered by the Company to the Holder thereof.  For purposes
                 of this Section 3.07, the Trustee shall act as the Paying
                 Agent."

                 SECTION 1.07.  Amendment to Section 4.04.  Section 4.04 of the
Indenture is hereby amended and restated in its entirety as follows:

                 "SECTION 4.04.  Maintenance of Consolidated EBITDA.

                                  (a)  The Company shall not permit the sum of
                 (i) Consolidated EBITDA for any period of four consecutive
                 fiscal quarters ending on any date set forth below plus (ii)
                 the Aggregate EBITDA Adjustment Amount as of such date to be
                 less than the amount set forth opposite such date:

<TABLE>
<CAPTION>

                        Date                               Amount                                
                        ----                            -----------                              
                   <S>                                  <C>                                      
                   December 30, 1996                    $33,000,000                              
                   March 31, 1997                        34,000,000                              
                   June 30, 1997                         35,000,000                              
                   September 29, 1997                    35,500,000                              
                   December 29, 1997                     36,000,000                              
                   March 30, 1998                        36,500,000                              
                   June 29, 1998                         37,000,000                              
</TABLE>

                                  (b)  The Company shall not permit the sum of
                 (i) Consolidated EBITDA for the period of two consecutive
                 fiscal quarters ending September





<PAGE>   7
                                                                               6



                 23, 1996 plus (ii) 50% of the Aggregate EBITDA Adjustment
                 Amount as of the last day of such period to be less than
                 $14,000,000.

                                  (c)  The Company shall not permit the sum of
                 (i) Consolidated EBITDA for any period of two consecutive
                 fiscal quarters ending after September 23, 1996 plus (ii) 50%
                 of the Aggregate EBITDA Adjustment Amount as of the last day
                 of such period to be less than $13,000,000."

                 SECTION 1.08.  Amendment to Section 4.08.  Section 4.08 of the
Indenture is hereby amended by (a) changing the number "120" contained in the
first sentence of paragraph (a) thereof to the number "90"; (b) inserting the
words "and within 45 days after the end of the Company's first, second and
third fiscal quarters of each fiscal year" after the words "the Company's
fiscal year" contained in the first sentence of paragraph (a) thereof; (c)
inserting the words "(or portion of the fiscal year ending with the fiscal
quarter covered by such Officers' Certificate, in the case of quarterly
certificates)" after each occurrence of the word "year" (other than the first
such occurrence) contained in the first sentence of paragraph (a) thereof; and
(d) deleting clause (iii) of paragraph (c) thereof (which clause (iii) ends
immediately before the words ", an Officers' Certificate") in its entirety.

                 SECTION 1.09.  Amendment to Section 4.13.  Clause (vi) of
paragraph (d) of Section 4.13 of the Indenture is hereby amended by (a) adding
a subclause reference "(1)" to the beginning thereof, (b) changing each
reference to "clause (vi)" contained in such newly designated subclause (1) to
the reference "subclause (1)" and (c) adding a new subclause (2) after the
amount "$15,000,000" contained therein which shall read in its entirety as
follows:

                 "and (2) Indebtedness consisting of Capital Lease Obligations
                 incurred in connection with any Sale/leaseback consummated in
                 order to comply with the requirements of Section 4.24 or 4.25
                 and any renewals, extensions, refinancings or replacements
                 thereof"

                 SECTION 1.10.  Amendment to Section 4.17.  Section 4.17 of the
Indenture is hereby amended by:

                 (a) amending and restating in its entirety the first proviso
        contained in clause (A) thereof as follows:

                 "provided, however, that (x) the Net Cash Proceeds which may
                 be so reinvested pursuant to any Asset Sale (other than a
                 Specified Sale-leaseback Transaction) shall not exceed 5% of
                 such Net Cash Proceeds (or, in the case of the Required Black
                 Angus Sale/leaseback Transaction, 10% of such Net Cash
                 Proceeds), and (y) the total Net Cash Proceeds which may be so
                 reinvested pursuant to all Asset Sales (other than Specified
                 Sale/leaseback Transactions) consummated after the
                 Supplemental Indenture Effective Date shall not exceed
                 $8,000,000"; and





<PAGE>   8
                                                                               7



                 (b) amending and restating in its entirety the penultimate
        proviso thereof as follows:

                 "; provided, further, that the Company may exclude from the
                 provisions of this Section 4.17, to the extent applicable, up
                 to $2,000,000 of Net Cash Proceeds which the Company has
                 elected to exclude from the obligation to make a Net Proceeds
                 Offer pursuant to and in accordance with Section 3.07(a) so
                 long as such Net Cash Proceeds are applied to prepay Working
                 Capital Loans, secure Letter of Credit Obligations or reduce
                 the outstanding amount of letters of credit under the Credit
                 Agreement".

                 SECTION 1.11.  New Covenants.  The Indenture is hereby amended
by adding the following Sections to the end of Article Four thereof:

                 "SECTION 4.24.  Black Angus Sale/leaseback Transaction.

                                  After July 15, 1996 and on or before
                 September 15, 1996, the Company and the relevant Subsidiaries
                 shall consummate a Sale/leaseback transaction with respect to
                 Black Angus restaurants generating gross cash proceeds equal
                 to at least $48,000,000 and Net Cash Proceeds equal to at
                 least $43,500,000, provided, that no more than 24 such
                 restaurants may be the subject of such Sale/leaseback
                 transaction for the purpose of complying with this Section
                 4.24.

                 SECTION 4.25.  Additional Asset Sales.

                                  After July 15, 1996 and on or before December
                 31, 1996, the Company and its Subsidiaries shall consummate
                 one or more Asset Sales (including Sale/leasebacks but
                 excluding the Required Black Angus Sale/leaseback Transaction)
                 generating Net Cash Proceeds equal to at least $25,000,000.

                 SECTION 4.26.  Senior Executive Compensation.

                                  The Company shall not permit the aggregate
                 base salaries of Anwar Soliman and Ralph Roberts (the "Senior
                 Executives") to exceed $1,938,575.  Commencing on the
                 Supplemental Indenture Effective Date, the rate at which the
                 salaries of the Senior Executives are earned shall be reduced
                 by an aggregate amount equal to 20% of the aggregate base
                 salaries of the Senior Executives then in effect (the
                 aggregate amount of any such reduction for any fiscal year or,
                 in the case of the 1996 fiscal year, the portion thereof since
                 the Supplemental Indenture Effective Date, being referred to
                 as the "Holdback Amount").  The Company shall not permit any
                 portion of the Holdback Amount or any bonuses or other form of
                 compensation (other than (a) the reduced base salaries and (b)
                 benefits of the type historically provided by the Company to
                 the Senior Executives (including life insurance, medical,





<PAGE>   9
                                                                               8



                 disability and automobile benefits)) to be paid to the Senior
                 Executives with respect to any fiscal year of the Company
                 until the audited financial statements of the Company for such
                 fiscal year have been delivered to the Trustee.  After such
                 audited financial statements have been so delivered, the
                 ability of the Company to pay such Holdback Amount and bonuses
                 to the Senior Executives shall be determined on the basis of
                 the sum of Consolidated EBITDA for the relevant fiscal year
                 plus the Aggregate EBITDA Adjustment Amount as of the last day
                 of such fiscal year, as set forth below:


<TABLE>
<CAPTION>
                 Consolidated EBITDA plus                   Holdback Amount Payment/
                 Aggregate EBITDA Adjustment Amount         Bonus Payment           
                 ----------------------------------         ------------------------
                 <S>                                        <C>
                 Less than $28,000,000                      The Company shall defer payment 
                                                            of the entire Holdback Amount.  
                                                            The Company shall pay no 
                                                            bonuses to the Senior Executives.

                 $28,000,000-$32,999,999                    The Company may pay one-half of 
                                                            the Holdback Amount.  The 
                                                            Company shall defer payment of 
                                                            the remaining one-half of the 
                                                            Holdback Amount.  The Company 
                                                            shall pay no bonuses to the Senior 
                                                            Executives.

                 $33,000,000-$39,999,999                    The Company may pay the entire 
                                                            Holdback Amount.  The Company 
                                                            shall pay no bonuses to the Senior 
                                                            Executives.


                 $40,000,000-$44,999,999                    The Company may pay the entire 
                                                            Holdback Amount.  In addition, 
                                                            the Company may pay bonuses to 
                                                            the Senior Executives in an 
                                                            aggregate amount not to exceed 
                                                            10% of the aggregate base salaries 
                                                            of the Senior Executives for the 
                                                            preceding fiscal year.

                 $45,000,000-$49,999,999                    The Company may pay the entire 
                                                            Holdback Amount.  In addition, 
                                                            the Company may pay bonuses to 
                                                            the Senior Executives in an 
                                                            aggregate amount not to exceed
</TABLE>





<PAGE>   10
                                                                               9




<TABLE>
                 <S>                                       <C>
                                                            20% of the aggregate base salaries 
                                                            of the Senior Executives for the 
                                                            preceding fiscal year.

                 $50,000,000 or above                       The Company may pay the entire 
                                                            Holdback Amount.  In addition, 
                                                            the Company may pay bonuses to 
                                                            the Senior Executives in an amount 
                                                            determined by the Board of 
                                                            Directors of the Company.
</TABLE>

                 Any Holdback Amount that is deferred as provided above may be
                 paid by the Company upon delivery to the Trustee of audited
                 financial statements of the Company in any subsequent year if
                 the sum of Consolidated EBITDA for the fiscal year covered by
                 such financial statements plus the Aggregate EBITDA Adjustment
                 Amount as of the last day of such fiscal year is at least
                 $36,500,000.  The Company shall not pay any Holdback Amount or
                 bonuses to the Senior Executives at any time when a Default or
                 Event of Default (other than solely pursuant to Section 4.04)
                 shall have occurred and be continuing."

                 SECTION 1.12.  Amendment to Section 6.01.  Section 6.01 of the
Indenture is hereby amended by adding the following words to the end of the
parenthetical contained in the last paragraph thereof:

                 "and other than in the case of any Default under Section 4.04,
                 4.24 or 4.25, which Defaults shall be Events of Default
                 without any requirement for the giving of notice and without
                 the passage of time specified in this paragraph"

                 SECTION 1.13.  Amendment to Section 8.01.  Paragraph (c) of
Section 8.01 of the Indenture is hereby amended by adding the words "and
Sections 4.24 through 4.26" after the reference "4.21" contained therein.

                 SECTION 1.14.  Deletion of Certain References to Section 4.04.
The Indenture is hereby amended by deleting each reference to Section 4.04 from
(a) the definition of "Paying Agent" contained in Section 1.01 thereof, (b)
Section 2.03 thereof, (c) Section 2.06 thereof and (d) the form of Option of
Holder to Elect Purchase.  In addition, Section 6.01 of the Indenture is hereby
amended by deleting the words "4.04 or" appearing before the reference to
Section 4.17 contained in the last paragraph thereof.

                 SECTION 1.15.  Deletion of References to Accelerated Payments.
The Indenture is hereby amended by (a) deleting the words "an Accelerated
Payment or" from paragraph (2) of Section 6.01 thereof and (b) deleting the
words "an Accelerated Payment and" from Section 7.05 thereof.  In addition,
each Security and Exhibit A-2 to the Indenture are hereby amended by deleting
the words ", including an Accelerated Payment" from paragraph 18 thereof.





<PAGE>   11
                                                                              10



                 SECTION 1.16.  Amendment to Paragraph 6 of the Securities and
the Form of Note.  Paragraph 6 of each Security and Exhibit A-2 to the
Indenture is hereby amended by adding the following sentence after the second
sentence thereof:

                 "In addition, the Company may credit against such sinking fund
                 payment 100% of the principal amount of any Securities
                 previously purchased by the Company pursuant to a Net Proceeds
                 Offer."

                 SECTION 1.17.  Amendment to Paragraph 8 of the Securities and
the Form of Note.  Paragraph 8 of each Security and Exhibit A-2 to the
Indenture is hereby amended and restated in its entirety as follows:

                 "8.      Maintenance of Consolidated EBITDA.

                                  The Indenture requires the Company to
                 maintain Consolidated EBITDA (subject to certain adjustments)
                 for certain periods specified therein at the levels specified
                 therein."

                 SECTION 1.18.  Amendment to Timing of Interest Payments and
Record Dates.   Each Security and Exhibit A-2 to the Indenture are hereby
amended by (a) deleting the dates listed after the caption "Interest Payment
Dates" and inserting, in lieu thereof, the dates "March 15, June 15, September
15 and December 15", (b) deleting the dates listed after the caption "Record
Dates" and inserting, in lieu thereof, the dates "March 1, June 1, September 1
and December 1" and (c) deleting the words "semi-annually on March 15 and
September 15 of each year" contained in paragraph 1 thereof and inserting, in
lieu thereof, the words "quarterly on March 15, June 15, September 15 and
December 15 of each year".

                 SECTION 1.19.  Amendment to Interest Rate.  The Indenture and
each Security and Exhibit A-2 to the Indenture are hereby amended by changing
each reference to the percentage "12%" to the percentage "13%".  In addition,
each Security and Exhibit A-2 to the Indenture are hereby amended by changing
the percentage "14%" contained in paragraph 1 thereof to the percentage "15%".


                                  ARTICLE TWO

                                 MISCELLANEOUS

                 SECTION 2.01.  Conditions Precedent; Reaffirmation of
Subsidiary Guarantee.  The effectiveness of this First Supplemental Indenture
is conditioned upon the receipt by the Trustee of (a) counterparts hereof
executed and delivered by the Company and each Subsidiary Guarantor and (b) a
satisfactory opinion of counsel stating that this First Supplemental Indenture
complies with the provisions of Section 9.02 of the Indenture and covering
other customary corporate matters, which opinion may be relied upon by each
person that is a Securityholder on the Supplemental Indenture Effective Date.
By its





<PAGE>   12
                                                                              11



execution and delivery of this First Supplemental Indenture, each Subsidiary
Guarantor reaffirms and restates its obligation set forth in Article 11 of the
Indenture.

                 SECTION 2.02.  Incorporation of Indenture.  All the provisions
of this First Supplemental Indenture shall be deemed to be incorporated in, and
made a part of, the Indenture; and the Indenture, as supplemented and amended
by this First Supplemental Indenture, shall be read, taken and construed as one
and the same instrument.

                 SECTION 2.03.  Headings.  The headings of the Articles and
Sections of this First Supplemental Indenture are inserted for convenience of
reference and shall not be deemed to be a part thereof.

                 SECTION 2.04.  Counterparts.  This First Supplemental
Indenture may be executed in any number of counterparts, each of which so
executed shall be deemed to be an original, but all such counterparts shall
together constitute but one and the same instrument.

                 SECTION 2.05.  Conflict with Trust Indenture Act.  If any
provision hereof limits, qualifies or conflicts with another provision hereof
which is required to be included in this First Supplemental Indenture by any of
the provisions of the Trust Indenture Act, such required provision shall
control.

                 SECTION 2.06.  Successors.  All covenants and agreements in
this First Supplemental Indenture by the Company and each Subsidiary Guarantor
shall bind their respective successors.  All covenants and agreements of the
Trustee in this First Supplemental Indenture shall bind its successor.

                 SECTION 2.07.  Separability Clause.  In case any provision in
this First Supplemental Indenture shall be invalid, illegal or unenforceable,
the validity, legality and enforceability of the remaining provisions shall not
in any way be affected or impaired thereby.

                 SECTION 2.08.  Benefits of First Supplemental Indenture.
Nothing in this First Supplemental Indenture, express or implied, shall give to
any person, other than the





<PAGE>   13
                                                                              12



parties hereto and their successors hereunder and the Holders, any benefit or
any legal or equitable right, remedy or claim under this First Supplemental
Indenture.

                 SECTION 2.09.  Terms Defined.  All terms defined elsewhere in
the Indenture have the same meanings herein.

                 SECTION 2.10.  Expenses.  The Company agrees to pay the
reasonable costs and expenses of the Trustee and the Holders, including the
reasonable expenses of one firm of counsel to certain of the Holders, in
connection with the negotiation and execution of this First Supplemental
Indenture.

                 SECTION 2.11.  Acknowledgement of Waiver, etc.  The Company
and the Trustee hereby acknowledge that, in connection with the Consent
Solicitation Statement, the holders of a majority in principal amount of
outstanding Securities have waived compliance with (a) the requirements of
Sections 4.04 and 4.08 of the Indenture (as in effect prior to giving effect to
this First Supplemental Indenture) and (b) the Consent Period requirement of
Section 9.02 of the Indenture.  The Company also hereby instructs the Trustee
to distribute to the Consenting Holders the Consent Payments (as each such term
is defined in the Consent Solicitation Statement) in the amounts, and at the
times, specified in the Consent Solicitation Statement.





<PAGE>   14
                                                                              13



                 IN WITNESS WHEREOF, the parties hereto have caused this First
Supplemental Indenture to be duly executed and attested, all as of the day and
year first above written.



                                        AMERICAN RESTAURANT GROUP, INC.


                                        By:  /s/  WILLIAM J. McCAFFREY, JR.
                                           ----------------------------------
                                           Name:  William J. McCaffrey, Jr.
                                           Title: Vice President and
                                                  Chief Financial Officer


                                        U.S. TRUST COMPANY OF CALIFORNIA, N.A.


                                        By:  /s/  SANDRA H. LEESS
                                           ---------------------------------
                                           Name:  Sandra H. Leess
                                           Title: Senior Vice President


                                        SUBSIDIARY GUARANTORS:

                                        ARG ENTERPRISES, INC.
                                        SPECTRUM FOODS, INC.
                                        SPOONS RESTAURANTS, INC.
                                        ARG PROPERTY MANAGEMENT CORPORATION
                                        GRANDY'S, INC.
                                        LOCAL FAVORITE, INC.


                                        By:  /s/  WILLIAM J. McCAFFREY, JR.
                                           ---------------------------------
                                           Name:  William J. McCaffrey, Jr.
                                           Title: Vice President and
                                                  Chief Financial Officer
                                           (for each of the above-listed
                                           Subsidiary Guarantors)