POWER OF ATTORNEY

        KNOW ALL BY THESE PRESENTS, that the undersigned, Olu Beck, hereby
constitutes and appoints each of Jolyn Sebree and Brian Purcell and each of them
acting individually, her true and lawful attorneys-in-fact to:

        1.   execute for and on behalf of the undersigned Forms 3, 4 and 5
relating to the Common Stock, par value $0.0001 per share, of Hostess Brands,
Inc. (the "Company") in accordance with Section 16(a) of the Securities Exchange
Act of 1934 (the "Exchange Act") and the rules thereunder;

        2.   do and perform any and all acts for and on behalf of the
undersigned which may be necessary or desirable to complete the execution of any
such Form 3, 4 or 5 and the timely filing of such form with the United States
Securities and Exchange Commission and any other authority, including Nasdaq;
and

        3.   take any other action of any type whatsoever in connection with the
foregoing which, in the opinion of such attorney-in-fact, may be of benefit to,
in the best interest of, or legally required by, the undersigned, it being
understood that the documents executed by such attorney-in-fact on behalf of
the undersigned pursuant to this Power of Attorney shall be in such form and
shall contain such terms and conditions as such attorney-in-fact may approve in
his or her discretion.

        The undersigned hereby grants to each such attorney-in-fact full power
and authority to do and perform all and every act and thing whatsoever
requisite, necessary and proper to be done in the exercise of any of the rights
and powers herein granted, as fully to all intents and purposes as such
attorney-in-fact might or could do if personally present, with full power of
substitution or revocation, hereby ratifying and confirming that such attorney-
in-fact, or his or her substitute or substitutes, shall lawfully do or cause to
be done by virtue of this power of attorney and the rights and powers herein
granted.  The undersigned acknowledges that the foregoing attorneys-in-fact, in
serving in such capacity at the request of the undersigned, are not assuming any
of the undersigned's responsibilities to comply with Section 16 of the Exchange
Act.

        This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Forms 3, 4, and 5 with respect to the
undersigned's holdings of and transactions in securities issued by the Company,
unless earlier revoked by the undersigned in a signed writing delivered to the
foregoing attorneys-in-fact.

        IN WITNESS WHEREOF, the undersigned caused this Power of Attorney to be
executed as of this 29th day of April, 2021.

                                        /s/ Olu Beck
                                        ----------------------------
                                        Olu Beck