These Peanut Butter S’mores Brownies are rich, fudgy, and layered with classic campfire flavor. A buttery graham cracker crust holds a chocolate brownie base filled with peanut butter cups and peanut butter chips, then everything is finished with toasted mini marshmallows.
Why You’ll Love This Recipe
This recipe combines three favorites in one pan: brownies, peanut butter, and s’mores. The graham cracker crust adds crunch, the brownie layer is soft and chocolatey, and the marshmallow topping gives every bite a sweet, toasted finish. It is perfect for parties, bake sales, family desserts, or weekend treats.
Ingredients
(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)
For the graham cracker crust:
1 cup graham cracker crumbs
2 tablespoons granulated sugar
6 tablespoons unsalted butter, melted
For the brownie layer:
1 cup unsalted butter, melted
1 cup granulated sugar
1/2 cup whole milk
1 teaspoon vanilla extract
2 large eggs
1 cup all-purpose flour
1/2 cup unsweetened cocoa powder
1 teaspoon baking powder
1 cup chopped peanut butter cups
1 cup peanut butter chips
For the topping:
1 bag mini marshmallows, 10 ounces
Directions
Preheat the oven to 350°F. Line a 9×13-inch baking pan with parchment paper and lightly grease it.
In a bowl, mix graham cracker crumbs, sugar, and melted butter until evenly combined. Press the mixture firmly into the bottom of the prepared pan. Bake for 8 minutes, then remove from the oven.
In a large bowl, whisk melted butter, sugar, milk, vanilla extract, and eggs until smooth.
Add flour, cocoa powder, and baking powder. Stir just until the batter comes together. Fold in the chopped peanut butter cups and peanut butter chips.
Spread the brownie batter evenly over the baked crust. Bake for 25 to 30 minutes, or until the center is set and a toothpick comes out with moist crumbs.
Sprinkle mini marshmallows evenly over the brownies. Return the pan to the oven for 3 to 5 minutes, until the marshmallows puff up. For a toasted top, broil briefly while watching closely.
Let the brownies cool before slicing.
Servings and timing
This recipe makes about 16 brownies.
Prep time: 20 minutes
Bake time: 35 to 43 minutes
Cooling time: 30 minutes
Total time: about 1 hour 30 minutes
Variations
Use chocolate chips instead of peanut butter chips for a deeper chocolate flavor. Add crushed graham crackers on top with the marshmallows for extra crunch. You can also swirl 1/3 cup creamy peanut butter into the brownie batter before baking.
Storage/Reheating
Store brownies in an airtight container at room temperature for up to 3 days or in the refrigerator for up to 5 days.
To reheat, warm one brownie in the microwave for 10 to 15 seconds. For a softer marshmallow topping, avoid overheating.
FAQs
Can I use a smaller pan?
Yes, but the brownies will be thicker and need extra baking time.
Can I make these ahead of time?
Yes, bake them one day ahead and store covered.
Can I use boxed brownie mix?
Yes, prepare the crust first, then add prepared brownie mix and toppings.
How do I know the brownies are done?
The center should look set, and a toothpick should come out with moist crumbs.
Can I freeze them?
Yes, freeze sliced brownies in an airtight container for up to 2 months.
Why did my marshmallows burn?
They were likely under the broiler too long. Watch them closely.
Can I skip the peanut butter cups?
Yes, use more peanut butter chips or chocolate chips instead.
Should the brownies cool before cutting?
Yes, cooling helps them slice cleanly.
Can I use mini peanut butter cups?
Yes, chop them slightly or fold them in whole.
Can I make the crust thicker?
Yes, increase graham crumbs to 1 1/2 cups and butter to 8 tablespoons.
Conclusion
Peanut Butter S’mores Brownies are a fun, rich dessert with layers of buttery graham cracker crust, fudgy chocolate brownie, peanut butter candy, and gooey marshmallows. They are easy to make, crowd-friendly, and perfect whenever you want a dessert that feels extra special.
Decadent peanut butter s’mores brownies featuring a buttery graham cracker crust, rich fudgy brownie layer with peanut butter cups and chips, and a gooey toasted marshmallow topping.
Ingredients
1 cup graham cracker crumbs
2 tablespoons granulated sugar
6 tablespoons unsalted butter, melted
1 cup unsalted butter, melted
1 cup granulated sugar
1/2 cup whole milk
1 teaspoon vanilla extract
2 large eggs
1 cup all-purpose flour
1/2 cup unsweetened cocoa powder
1 teaspoon baking powder
1 cup chopped peanut butter cups
1 cup peanut butter chips
1 bag (10 oz) mini marshmallows
Instructions
Preheat oven to 350°F and line a 9×13-inch pan with parchment paper.
Mix graham cracker crumbs, sugar, and melted butter, then press into the pan.
Bake crust for 8 minutes and set aside.
In a bowl, whisk melted butter, sugar, milk, vanilla, and eggs until smooth.
Stir in flour, cocoa powder, and baking powder until combined.
Fold in peanut butter cups and peanut butter chips.
Spread batter over crust evenly.
Bake for 25–30 minutes until center is set.
Top with mini marshmallows and bake 3–5 more minutes until puffed.
Broil briefly for a toasted finish if desired, watching closely.
Cool completely before slicing.
Notes
Do not overbake to keep brownies fudgy.
Watch marshmallows closely under broiler to avoid burning.
Use chocolate chips instead of peanut butter chips for variation.
Swirl peanut butter into batter for extra richness.
