These chocolate marshmallow bars are the perfect blend of chewy, gooey, and crunchy, making them an irresistible treat for any occasion. A rich, fudgy brownie base is topped with a layer of melty marshmallow fluff and finished with a crispy, chocolatey topping that adds just the right amount of crunch. Whether you’re making these for a potluck, bake sale, or a weekend treat, they’re guaranteed to disappear fast!
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There’s something magical about the combination of chocolate and marshmallow. These chocolate marshmallow bars take that classic pairing to the next level with a fudgy brownie base, a gooey marshmallow layer, and a crispy, chocolatey topping that adds just the right amount of crunch.
If you love rich, chocolatey desserts, you’ll definitely want to try a few more of our favorite treats! For a sweet and salty twist, these Caramel Peanut Bars are a must—packed with gooey caramel and crunchy peanuts, they’re completely addictive.
If you’re in the mood for something ultra-decadent, this Earthquake Cake is a chocolate lover’s dream, with swirls of cream cheese, coconut, and pecans baked right in.
And for those who love a classic, my Chocolate Walnut Brownies are rich, fudgy, and filled with crunchy walnuts for the perfect bite. No matter which one you choose, you're in for a seriously delicious treat!
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What You'll Love About This Recipe
The perfect texture combination – Fudgy, gooey, and crispy all in one bite!
Crowd-pleaser – Everyone from kids to adults will love these chocolate and marshmallow treats.
Easy to make – Simple ingredients and no complicated steps make this a great recipe for beginners.
Make-ahead friendly – These marshmallow bars store well and are great for prepping ahead of time.
Ingredients
Unsalted butter – Gives the bars a rich, buttery flavor. Make sure it's softened for easy mixing.
Granulated sugar – Sweetens the base and helps create a soft, chewy texture.
Eggs – Bind everything together and add moisture.
Vanilla extract – Adds warmth and enhances the chocolate flavor.
All-purpose flour – Provides structure to the base. Spoon and level it to avoid a dense batter.
Unsweetened cocoa powder – Gives that deep chocolate flavor. Use a high-quality cocoa for the best results.
Baking powder – Helps the base rise slightly so it doesn’t become too dense.
Salt – Balances the sweetness and enhances the chocolate.
Marshmallow fluff – The gooey middle layer that makes these bars extra delicious!
Rice crispy cereal – Gives the bars a light, crispy crunch that contrasts perfectly with the soft layers.
Semi-sweet chocolate chips – Melt into a rich, chocolatey topping. Dark chocolate works too if you prefer a less sweet option.
Miniature marshmallows – These add extra gooeyness and a classic marshmallow flavor.
Unsalted butter – Helps the topping melt smoothly and creates a glossy finish.
See recipe card for quantities.
Instructions
Preheat and Prep: Preheat your oven to 350°F. Line a 15x10x1-inch baking sheet with foil and give it a generous spray of non-stick cooking spray.
Mix the Wet Ingredients: In a mixing bowl, cream together the softened butter and sugar until well combined. Beat in the eggs one at a time, ensuring each is fully incorporated before adding the next. Stir in the vanilla extract.
Combine the Dry Ingredients: In a separate bowl, whisk together the flour, cocoa powder, baking powder, and salt. Gradually add the dry ingredients to the wet mixture, stirring until fully blended.
Mix the dry into the Wet Ingredients: Now you can mix your dry ingredients into your wet ingredients.
Bake the Base: Spread the batter evenly into your prepared pan. Bake for 15-18 minutes, or until a toothpick inserted in the center comes out mostly clean.
Add the Marshmallow Layer: As soon as the base comes out of the oven, immediately spread the marshmallow fluff over the top while it’s still warm. This makes it easier to spread! Let it cool for about 30 minutes before adding the topping.
Make the Topping: In a saucepan over medium heat, melt the chocolate chips, butter, and miniature marshmallows together, stirring constantly until smooth.
Add the Crunch: Once melted, remove from heat and stir in the rice crispy cereal until evenly coated.
Assemble: Working quickly, scoop the chocolate mixture over the marshmallow layer and spread it evenly before it starts to firm up.
Chill and Serve: Refrigerate until the top is set, about 30 minutes. Cut into bars and enjoy!
Hint: To make spreading the marshmallow fluff easier, lightly warm it in the microwave for 10-15 seconds or spray your spatula with non-stick spray. This prevents sticking and helps it glide smoothly over the warm base!
Substitutions
- Rice crispy cereal → Crushed graham crackers for a s’mores vibe.
- Semi-sweet chocolate chips → Milk chocolate or dark chocolate for a sweeter or more intense flavor.
- Marshmallow fluff → Melted mini marshmallows for a slightly different texture.
- Butter → Coconut oil if you want a subtle coconut flavor.
Variations
Want to try some variations on this recipe? Here are some of our favorite ideas.
- Peanut Butter Twist: Add ½ cup of peanut butter to the melted chocolate mixture before stirring in the rice crispies.
- Nutty Crunch: Stir in chopped almonds, pecans, or walnuts for added texture.
- Extra Chocolatey: Mix in some white chocolate chips or drizzle white chocolate over the top.
- Salted Caramel: Swirl caramel sauce over the marshmallow layer before adding the topping.
Storage
Have leftover bars you'd like to store, here's our tips.
Room Temperature: Store the bars in an airtight container at room temperature for up to 4 days. They hold up well without refrigeration, making them great for gifting or parties.
Fridge: If you prefer a firmer texture, store them in the refrigerator for up to a week. Just let them sit at room temperature for a few minutes before eating so the layers soften slightly.
Freezer: For longer storage, wrap individual bars in plastic wrap and store in an airtight container in the freezer for up to 2 months. Thaw at room temperature before enjoying.
Top tip
Work fast with the topping! The chocolate mixture will start to firm up quickly once off the heat, so have everything ready to go before you spread it over the marshmallow layer.
FAQ
Yes! You can melt about 5 cups of mini marshmallows over low heat with a little butter to create a spreadable consistency.
Yes, you can use milk chocolate for a sweeter topping or dark chocolate for a more intense chocolate flavor.
The topping starts to set quickly as it cools. Work fast and spread it immediately after mixing in the crispy rice cereal.
Chill the bars first, then use a sharp knife coated with non-stick spray to get clean, neat slices.
Butter is best for flavor and texture, but margarine can work in a pinch. The taste and consistency may vary slightly.
Related
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Recipe
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Chocolate Marshmallow Bars
Ingredients
For the Base:
- ¾ cup unsalted butter softened
- 1 ½ cups granulated sugar
- 3 large eggs
- 1 teaspoon vanilla extract
- 1 ⅓ cups all-purpose flour
- 3 tablespoons unsweetened cocoa powder
- ½ teaspoon baking powder
- ½ teaspoon salt
- 1 tub marshmallow fluff 7 ounces
For the Topping:
- 1 ⅓ cups semi-sweet chocolate chips
- 1 ½ to 2 cups miniature marshmallows
- 3 tablespoons unsalted butter
- 2 cups rice crispy cereal
Instructions
- Preheat oven to 350°F. Line a 15x10x1-inch baking sheet with foil and spray with non-stick spray.
- Make the base: Cream butter and sugar. Mix in eggs one at a time, then add vanilla. In a separate bowl, whisk flour, cocoa powder, baking powder, and salt. Combine wet and dry ingredients.
- Bake: Spread batter in the pan and bake for 15-18 minutes until a toothpick comes out clean.
- Add marshmallow layer: While warm, spread marshmallow fluff evenly over the base. Let cool for 30 minutes.
- Prepare topping: Melt chocolate chips, butter, and marshmallows over medium heat, stirring until smooth. Mix in rice crispy cereal.
- Assemble: Spread topping over the cooled marshmallow layer.
- Chill and serve: Refrigerate until set, then cut into bars and enjoy.
Notes
Nutrition
These chocolate marshmallow bars are the ultimate crowd-pleaser, combining layers of rich chocolate, gooey marshmallow, and a crispy, chocolatey topping for a texture-packed bite that’s impossible to resist.
Whether you're making them for a special occasion or just satisfying a sweet tooth, they’re guaranteed to be a hit. Plus, they store well, so you can enjoy them all week long—if they last that long!
Give them a try, and don’t forget to check out some of my other chocolate-packed desserts for even more delicious inspiration. Happy baking!
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