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If you’ve ever had a marshmallow brownie I bet you’re hitting the Print Recipe button right now because they are GOOD! A rich chocolate brownie is topped with MOUNDS of marshmallowy fluff (you have to make your own, it’s easy and so tasty) then drizzled with more chocolate. I did a swirl but some people literally flood the top with ganache, there is no wrong way to go here. Anyhow You’re probably going to ant to double the batch as people will ask you to bring these to work/school/their house.

A photo of a Marshmallow Brownie on a plate.

The topping is really just Italian meringue with one key addition. Light corn syrup makes this ultra-marshmallowy. I wish I knew the science behind this but I came across this after some experimentation.

Can you put marshmallows in brownie mix?

YES! The soft gooey texture and sweetness of the marshmallow pairs wonderfully with the rich brownie. Add half a bag of mini marshmallows to the prepared batter or cover the brownie with them just before it’s finished backing.

what can you do With Marshmallows?

Whip up a batch of marshmallow fluff! If you’re in a hurry an easy hack for a similar taste is to pile some marshmallows on top of the brownie toward the end of baking and they’ll melt in the oven. You can also broil for a few minutes.

What Desserts Can you Make with Marshmallows?

Ultimate s’mores with homemade marshmallows

S’more’s cake

Hot chocolate marshmallow cookies

Rocky road cupcakes

Pro tip, don’t add gelatine to your molten sugar! Feel free to experiment with flavoring the marshmallow topping and swirling extra ingredients in. This could have some peppermint for a holiday twist or a peanut butter syrup for some good old American zazz! ?  Hope you enjoy!

Steps to Make This Marshmallow Brownie

A photo showing steps on how to make a marshmallow brownie.

How do you make Marshmallow Fluff Brownies?

  1. For the brownie; Preheat the oven to 350 degrees and prep a 9×13-inch baking pan with parchment paper. In a bowl, combine the eggs and sugar then mix them together. Sift the cocoa powder, flour, baking powder and salt to a bowl and give it a whisk.
  2. Combine the dry ingredients with the egg and sugar mixture. Toss in the chocolate chips and the melted butter. Add the batter to the prepped pan, smooth it out and bake for about 30 minutes.
  3. For the marshmallow; Beat the egg whites and 2/3 cup of sugar until it forms soft peaks. In a medium saucepan, add the remaining sugar, 2/3 cup of water and corn syrup, then place on low heat. Maintain at medium high heat and stir until the sugar melts and becomes clear. Heat until temperature reads 235-240F.
  4. Drizzle the sugar into the mixer (running on low) immediately once it is ready. Now run the mixer until the marshmallow is cool.
  5. For the Assembly; Once the brownie has cooled, pile the marshmallow fluff on and smooth it out using a spatula. Melt 1/3 cup of semi sweet chocolate and about 2 tablespoons of cream together.
  6. pipe the chocolate ganache all over the top and use a toothpick or a skewer to create a more marbleized pattern of swirls. Enjoy!

If you’ve tried this marshmallow brownie then don’t forget to rate the recipe and let me know how you got on in the comments below, I love hearing from you!

Marshmallow Brownie

Author: John Kanell
Servings: 10
Prep Time: 25 minutes
Cook Time: 30 minutes
Total Time: 1 hour 5 minutes
Marshmallow Brownie
4.92 from 47 votes
The most decadent brownie I have had. It's topped with a thick marshmallowy layer and then drizzled with more chocolate.

Ingredients 

INGREDIENTS:

For the Marshmallow:

  • 8 egg whites room temperature
  • 1/2 cup water 120ml
  • 2 2/3 cups sugar 550g, divided
  • 1/4 cup light corn syrup 60mL
  • 2 tsp vanilla extract 10mL

For the Brownie:

  • 2 cups granulated sugar 400g
  • 2 eggs
  • 4 tablespoons cocoa powder 30g
  • 1 cup flour 120g
  • 1 teaspoon baking powder 4g
  • 2 teaspoon salt 12g
  • 2 cup dark chocolate chips 350g
  • 1 cup melted butter 225g

For the Chocolate Swirls

  • 2/3 cup semisweet chocolate 115g
  • 4 tbsp heavy cream 60mL
  • 1/4 tsp cream of tartar optional

Instructions

INSTRUCTIONS:

    For the Brownie:

    • Preheat the oven to 350 degrees F and prep a 9x13-inch baking pan with parchment paper.
    • In a bowl, combine eggs and sugar. Mix together.
    • Sift cocoa powder, flour, baking powder and salt into a separate bowl. Mix again.
    • Combine with egg and sugar mixture.
    • Toss in chocolate chips and melted butter.
    • Add batter to pan and smooth.
    • Bake for about 30 minutes.

    For the Marshmallow:

    • Beat the egg whites and 2/3 cup of sugar until soft peaks form. Add cream of tartar if using.
    • In a medium saucepan add the remaining sugar, 2/3 cup water and corn syrup, then place on low heat.
    • Stir until the sugar melts and becomes clear.
    • Maintain at medium high heat until temperature reads 235-240F.
    • Drizzle the sugar into the mixer immediately.
    • Add vanilla and run mixer until marshmallow is cool/tepid. 

    For the Assembly:

    • Melt 1/3 cup semi sweet chocolate and about 2 tablespoons of cream together. Set aside.
    • Once the brownie has cooled, pile the marshmallow fluff on and smooth it out using a spatula. 
    • Pipe the chocolate ganache all over the top and use a toothpick or skewer to create a more marbleized pattern of swirls. 

    Notes

    Recipe adapted from www.frederikkewaerens.com

    Nutrition

    Serving: 1g Calories: 370kcal Carbohydrates: 67g Protein: 7g Fat: 13.7g Saturated Fat: 3g Polyunsaturated Fat: 5.2g Monounsaturated Fat: 4g Cholesterol: 31mg Sodium: 223mg Potassium: 318mg Fiber: 4g Sugar: 47g Vitamin A: 50IU Calcium: 70mg Iron: 2.8mg

    *Nutrition Disclaimer

    Course: Dessert
    Cuisine: American

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    In the YouTube video, I used four eggs to make this brownie and it came out great, but I usually use two! 

    IF YOU LOVE THIS RECIPE TRY THESE OUT!

    Chocolate Cheesecake Brownies

    Brownie Recipe

    Hot Chocolate Marshmallow Cookies

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