PREHEAT oven to 350° F. Line baking sheet with foil. Arrange 24 graham cracker squares on prepared baking sheet; set aside.
BAKE cookie dough on another baking sheet according to package instructions. Cool for 2 minutes on baking sheet. Remove cookies from baking sheet and place one warm cookie on each graham cracker square on foil. Top each cookie with one marshmallow half.
BAKE for 1 to 2 minutes or until marshmallows are soft. Immediately top s’mores with remaining graham cracker squares.