Marshmallow Cocoa Puff Brownies
These Marshmallow Cocoa Puff Brownies are a decadent chocolate dessert bar recipe made with a fudgy brownie base topped with gooey marshmallows and crispy cocoa puffs. It’s an easy dessert recipe perfect for dessert trays.
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These brownies are a fun dessert to serve for birthday parties, bake sales, potlucks, family movie nights, and holiday gatherings. It’s an easy make-ahead dessert you can make!
These brownies pair perfectly with a cold glass of milk, a scoop of vanilla ice cream, or other chocolate treats. Try serving them alongside Chocolate Peanut Butter Rice Krispies Treats or Easy Oreo Dessert Bars.
How to Make Marshmallow Cocoa Puff Brownies
Ingredients you’ll need for brownie batter
Ingredients you’ll need for marshmallow topping
Step-by-Step Guide
1. Start by preheating your oven to 350°F (175°C). Line your 8×8 baking dish with parchment paper so your brownies come out perfectly.
2. In a saucepan, melt your unsalted butter until it turns a beautiful golden brown and smells nutty.
3. Pour this browned butter into a large mixing bowl. Add your semisweet chocolate pieces and let it sit for a few seconds before stirring.
4. Now it’s time to add the sugars and salt! Whisk them in until fully combined. Add in the vanilla extract and eggs, and whisk again until smooth and shiny.
5. Fold in the cocoa powder and flour until your batter comes together into a thick, fudgy mixture.
6. Transfer the brownie batter into your prepared baking dish, spreading it out evenly. Pop them in the oven and bake for 35-40 minutes. You’ll know they’re ready when a toothpick comes out clean. Let these brownies cool completely once they’re done.
7. While the brownies are cooling, it’s time to make the topping! In a large pot, melt the butter over medium heat. Once melted, add in your marshmallows, stirring every minute or so until they’re smooth and gooey.
8. Stir in the cocoa puff cereal, coating it evenly with the marshmallow mixture.
9. Once your marshmallow cocoa puff mixture is ready, pour it over the cooled brownies. Use a spatula to press the mixture evenly into the dish, making sure it’s well spread out.
10. Let the brownies set at room temperature for about an hour to allow the topping to firm up.
11. Once they’re cooled, grab a sharp knife and cut them into squares.
Serve & Enjoy!
Important Recipe Notes
- Let the brownies cool completely before adding the topping. If the brownies are still warm, the marshmallow mixture can slide around and become messy instead of setting properly.
- Don’t overbake the brownies. Start checking them around the 35-minute mark. A toothpick should come out with a few moist crumbs, not wet batter, for the fudgiest texture.
- Stir the marshmallows frequently while melting. This helps prevent scorching and creates a smooth, evenly melted mixture for the topping.
- Work quickly once the cereal is mixed in. The marshmallow mixture begins to set fast, so spread it over the brownies as soon as the cocoa puffs are coated.
- Grease hands or a spatula lightly to make it easier to press the sticky marshmallow cereal mixture evenly over the brownies.
- Allow enough time for the topping to set. Let the brownies rest at room temperature for at least 1 hour before slicing for clean, neat squares.
- Line the baking pan with parchment paper. This makes removing and cutting the brownies much easier and helps prevent sticking.
- Store leftovers in an airtight container. They will stay fresh at room temperature for up to 3 days or in the refrigerator for up to 1 week.
- For cleaner cuts, lightly grease your knife. Wipe the blade between slices to keep the marshmallow topping from sticking.
Marshmallow Cocoa Puff Brownies
Ingredients
For Brownie Batter
- ½ cup unsalted butter , browned
- 4 ounces semisweet chocolate bar
- ½ cup white granulated sugar
- ½ cup brown sugar
- ½ tsp salt
- 3 eggs
- 1 tsp vanilla extract
- ½ cup cocoa powder
- ½ cup all-purpose flour
For Marshmallow Topping
- 10 ounce bag of marshmallows
- 5 tbsp unsalted butter
- 3 cups cocoa puff cereal
Instructions
- Start by preheating your oven to 350°F (175°C). Line your 8×8 baking dish with parchment paper so your brownies come out perfectly.
- In a saucepan, melt your unsalted butter until it turns a beautiful golden brown and smells nutty.
- Pour this browned butter into a large mixing bowl. Add your semisweet chocolate pieces and let it sit for a few seconds before stirring.
- Now it’s time to add the sugars and salt! Whisk them in until fully combined. Add in the vanilla extract and eggs, and whisk again until smooth and shiny.
- Fold in the cocoa powder and flour until your batter comes together into a thick, fudgy mixture.
- Transfer the brownie batter into your prepared baking dish, spreading it out evenly. Pop them in the oven and bake for 35-40 minutes. You’ll know they’re ready when a toothpick comes out clean. Let these brownies cool completely once they’re done.
- While the brownies are cooling, it’s time to make the topping! In a large pot, melt the butter over medium heat. Once melted, add in your marshmallows, stirring every minute or so until they're smooth and gooey.
- Stir in the cocoa puff cereal, coating it evenly with the marshmallow mixture.
- Once your marshmallow cocoa puff mixture is ready, pour it over the cooled brownies. Use a spatula to press the mixture evenly into the dish, making sure it’s well spread out.
- Let the brownies set at room temperature for about an hour to allow the topping to firm up.
