In a large mixing bowl, combine the graham cracker crumbs, brown sugar, granulated sugar, melted butter, and peanut butter. Stir until the mixture forms a cohesive dough.

Preheat your oven to 350°F (175°C). Line an 8x8-inch baking dish with parchment paper. Press half of the cookie dough evenly into the prepared dish to form a bottom crust.

Layer the chocolate bars on top of the crust, breaking them as needed. Spoon the marshmallow creme over the chocolate evenly.

Spread the remaining cookie dough over the marshmallow layer, sealing the edges carefully.

Bake for about 30 minutes, or until the top is golden brown. Let cool in the pan for about 15-20 minutes.

Refrigerate the bars for cleaner slices and serve.