Ultimate Sheet Pan S'Mores Brownie Bars for a Crowd
These Sheet Pan S'Mores Brownie Bars have become one of our favorite summer desserts. They have everything we love about the classic campfire treat. But instead of standing around the fire roasting marshmallows for twenty people, you bake one big pan and let everyone help themselves.
Servings: 24 Servings
Calories: 432kcal
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Ingredients
Graham Cracker Crust
- 3 Cups Graham Cracker Crumbs about 3 sleeves
- 2/3 Cup Butter melted
- 6 Tablespoons Granulated Sugar
Brownie Layer
- 32.6 Ounces Brownie Mix 2 boxes (9x13 size)
- 2 Tablespoons Water
- ½ Cup Vegetable Oil
- 2 Large Eggs
S'Mores Topping
- 6 Cups Mini Marshmallows
- 6 Graham Cracker Sheets broken into pieces
- 1 Cup Milk Chocolate Chips
- 4 Chocolate Bars broken into squares
Instructions
How to Make Sheet Pan S'Mores Bars
- Preheat your oven to 350°F and generously grease a half-sheet pan.
- Mix together the graham cracker crumbs, melted butter, and sugar until everything resembles damp sand. Firmly press the mixture into the prepared pan and bake for 10 minutes.3 Cups Graham Cracker Crumbs, 2/3 Cup Butter, 6 Tablespoons Granulated Sugar
- Meanwhile, in a large bowl, add both brownie mixes, water, oil, and eggs. Mix until well blended. Spread the batter evenly over the baked crust and return the pan to the oven. Bake for 30 to 35 minutes, or until a toothpick inserted near the center comes out with only a few moist crumbs.32.6 Ounces Brownie Mix, 2 Tablespoons Water, ½ Cup Vegetable Oil, 2 Large Eggs
- Scatter the marshmallows, broken graham crackers, chocolate chips, and Hershey bar pieces over the warm brownies.6 Cups Mini Marshmallows, 6 Graham Cracker Sheets, 1 Cup Milk Chocolate Chips, 4 Chocolate Bars
- Move the pan to an upper oven rack and broil for 2 to 3 minutes until the marshmallows are beautifully toasted and golden brown. Stay nearby—broilers can go from perfectly browned to burnt in seconds.
- Allow the bars to cool completely before slicing. For the cleanest cuts, refrigerate the pan for about 20 minutes first. Cut into 24 squares.
Notes
Tips for Success
- Press the crust firmly so it doesn't crumble when sliced.
- Don't overbake the brownies—they should stay slightly fudgy.
- Watch the broiler carefully. Marshmallows toast quickly.
- Spray your knife with cooking spray or wipe it with a warm damp towel between cuts for bakery-style slices.
- Let the bars cool completely before cutting.
Nutrition
Calories: 432kcal | Carbohydrates: 61g | Protein: 3g | Fat: 20g | Saturated Fat: 8g | Polyunsaturated Fat: 3g | Monounsaturated Fat: 6g | Trans Fat: 0.2g | Cholesterol: 14mg | Sodium: 256mg | Potassium: 82mg | Fiber: 1g | Sugar: 38g | Vitamin A: 160IU | Vitamin C: 0.003mg | Calcium: 22mg | Iron: 2mg