S'mores Peanut Butter Cup Crunch Bars turns traditional s'mores up a notch with this irresistible treat. Graham cracker cookie. Thick marshmallow middle. Crunchy chocolate peanut butter top. Pretty sure you can bribe any chocolate peanut butter lovers with these bars. Once upon a time, I made these marshmallow brownies. Fudgy brownies. Thick, gooey marshmallow layer.