- 6 tablespoons butter, melted
- 1 ½ cups graham cracker crumbs
- 2 tablespoons sugar
- pinch salt
- 1 brownie mix
- 4 cups large marshmellows
1. Position a rack in the lower third of the oven and heat oven to 325 degrees F. Line an 8 by-8-inch square baking pan with foil so it hangs over the edges by about 1 inch.
2. For the crust: Lightly butter the foil with some of the melted butter. Stir the rest of the butter together with the crumbs, sugar, and salt in a medium bowl. Press the crumb mixture evenly over the bottom of the pan. Bake until golden brown, about 20 minutes.
3. Mix brownie according to package. Pour batter into the prepared pan. Bake until the top is crispy and a toothpick inserted into the middle comes out mostly clean, with a few crumbs, according to package instructions.
4. Remove from the oven and carefully position a rack about 6 inches from the broiler and preheat on low. Layer marshmallows across the top and toast under the broiler until golden, (keep an eye on it, it can go quick), about 2 minutes. Cool on a rack, gently removing the brownies from the pan using the aluminum flaps. Carefully separate any marshmallow from the foil and fold away. Cut into 12 (2-inch) squares.