Follow these simple steps at home to make your very own Marshmallow Brownies with mini marshmallows! Fudgy brownies made with cocoa powder are topped with a layer of mini marshmallows and then frosted with a decadent fudge icing. Such a fun twist on classic chocolate brownies! Yields 16 squares.

The inside of a chocolate fudge brownie with marshmallow swirl.
The mini marshmallows in these brownies make them extra gooey.

As a trained pastry chef, I know a good scratch-made brownie recipe when I see one. I also always found baking marshmallows fascinating! The texture is just so much fun to play with. So tada! I bring you a super easy recipe for marshmallow brownies!

Ive used marshmallows as ingredients in recipes like these S’mores brownies, marshmallow frosting (which you can also slather on top of these,) or even top hot chocolate cupcakes with them for a fun cupcake treat!

In this recipe, mini marshmallows are poured on top of warm fudgy brownies and then toasted up to make them gooey and brown. Then these cocoa powder brownies are slathered with this top rated, 5 star brownie frosting that just takes it over the top! Brownies with icing are so much better than without!

I don’t recommend mixing mini marshmallows into the brownie batter because when I tried that, the marshmallows just melted. There were no white marshmallowy puffs throughout the brownies and there was no significant marshmallow taste.

Best to stick with just pouring them on top of baked brownies!

You can even do the same to other brownie recipes like these Red Velvet Brownies, homemade Cosmic brownies, or Dairy Free Brownies!

INGREDIENTS NEEDED

Ingredients for marshmallow brownies.
Mini marshmallows are preferred for this recipe but you can use the larger ones too.
  • Unsalted Butter – Moistens the brownie batter giving it a fudgy texture along with a buttery flavor.
  • Semi-Sweet Chocolate Chips – Adds a rich dark chocolate flavor to the marshmallow brownies when melted with butter.
  • Granulated Sugar – Sweetens the marshmallow brownies to perfection.
  • Vanilla Extract – Enhances the flavor of brownies, making them even more delicious.
  • Eggs – Binds all the ingredients together, creating a thick batter giving marshmallow brownies structure when baking.
  • All-Purpose Flour – Helps create a soft and thick marshmallow brownie batter.
  • Salt – Enhances all of the other flavors in the brownies that help bring out the sweetness of the chocolate.
  • Cocoa Powder – Gives a deep, dark chocolate flavor and enhances the brown chocolate color.
  • Mini Marshmallows – These fluffy treats are topped onto the baked brownies to create a delicious texture and flavor.
  • Brownie Frosting– The frosting ingredients are listed below, it takes less than 5 minutes to make!

For Frosting:

  • Unsalted Butter – Creates the thick creamy base of the frosting.
  • Cocoa Powder – Adds chocolate flavor and brown color.
  • Confectioners Sugar – This finely milled sweetener adds thickness to the frosting as well as gives it a sweet flavor.
  • Milk – Used to thin out the frosting as needed to make it the perfect consistency.

HOW TO MAKE MARSHMALLOW BROWNIES

Prepare for baking: Preheat the oven to 350° F and line an 8×8 inch pan with parchment paper or spray with nonstick baking spray. Set aside.

Melt the butter and chocolate: Add the butter and chocolate chips to a microwave-safe small bowl and heat on high for 30-second increments, stirring until the chocolate is completely melted.

Mix the eggs and sugar: Add the sugar and eggs to a medium mixing bowl. Using an electric mixer or stand mixer with the whisk attachment, beat together for four minutes or until the mixture is fully combined. Then, add the chocolate and butter mixture, gently folding in with a spatula. Add the vanilla extract and mix until combined.

Add the dry ingredients: To the wet ingredients, add the flour, cocoa powder, sugar, and salt. Mix the brownie batter together gently until it’s fully combined but not overworked.

Bake and add marshmallows: Pour the brownie batter into the prepared baking pan and bake for 26-28 minutes. Remove the brownies, then add the mini marshmallows on top. Bake for an additional 3 minutes in the oven to set, or use a kitchen torch to create a toasted marshmallow look.

Fudge brownie batter in a glass bowl.
Make the brownie batter in a medium sized bowl.
Fudgy brownie batter in a 8x8 pan.
Bake for 26-28 minutes.

Make the brownie frosting: In a large bowl, melt the butter 30 seconds at a time in the microwave until fully melted. Add in the cocoa powder and whisk until smooth. Add the milk and powdered sugar and mix.

Frost the brownies: As soon as the frosting is made, spread it on top of the brownies quickly as the frosting will harden. It’s ok to do this when the brownies are still a little warm. Enjoy!

Using an oven instead of kitchen torch

If you don’t have a kitchen torch, bake marshmallows in the oven for an extra 3 minutes, but make sure that the marshmallows don’t burn. Marshmallows are very delicate and can only withstand a few minutes in the oven. Be sure to check them closely and remove them from the oven as soon as they start to brown.

I do not recommend broiling your brownies unless you are seriously watching them the whole time. They only need 20-30 seconds of broil time and can easily catch fire if left for longer. The 3 minutes is only if your oven is on bake at 350!

Recipe Tips

  • If the frosting is too thick, add a teaspoon more milk at a time until you reach desired consistency.
  • The brownie frosting hardens quickly, so make sure to frost right away. It’s ok to do it while the brownies are still warm.
  • If you only have larger marshmallows, cut them in quarters. It’s hard to frost them with the brownie frosting because they will be too large. I have not made this recipe with marshmallow fluff.
A marshmallow brownie on its side on a white plate.

STORAGE AND FREEZING

Storage: Once the brownies are cooled and the frosting has hardened. You can store them in an airtight container on the counter for up to 5 days.

Freezing: You can freeze these too! Wrap them with parchment paper or aluminum foil and place them in a freezer-safe bag. They can last up to 3 months in the freezer. Be sure to thaw overnight before serving.

marshmallows are very delicate and can only withstand a few minutes in the oven. Be sure to check them closely and remove them from the oven as soon as they start to brown.

The inside of a chocolate fudge brownie with marshmallow swirl.
No ratings yet

How to Make Homemade Marshmallow Brownies

Follow these simple steps at home to make your very own Marshmallow Brownies with mini marshmallows! Fudgy brownies made with cocoa powder are topped with a layer of mini marshmallows and then frosted with a decadent fudge icing. Such a fun twist on classic chocolate brownies! Yields 16 squares.

Ingredients

  • 1/2 cup (113.5 g) butter
  • 6 oz (170.1 g) semi sweet chocolate chips, about 1 heaping cup
  • 1 cup (200 g) granulated sugar
  • 3 (3) eggs, large
  • 1 tsp (1 tsp) vanilla extract
  • 1/2 cup (62.5 g) flour
  • 1/4 cup (21.5 g) cocoa powder
  • 1/2 tsp (0.5 tsp) salt
  • 2 cups (100 g) mini marshmallows, or 10 oz bag

For Frosting:

  • ¼ cup (56.75 g) unsalted butter, 56g
  • cup (28.67 g) cocoa, 35g
  • 2 cups (240 g) confectioners sugar, 227g
  • 3 tbsp (3 tbsp) milk

Instructions
 

  • Preheat the oven to 350° F and line an 8×8 inch pan with parchment paper or spray with nonstick baking spray.
  • In a microwave safe bowl combine the 1/2 cup butter and 6 oz chocolate. Microwave for 30 seconds at a time stirring in between until the chocolate is melted. About 90 seconds total. Let the chocolate cool for 2 minutes.
  • In a medium bowl add the 1 cup sugar and 3 large eggs and whip on high speed using an electric mixer for 3 minutes. You can use a hand mixer or a stand mixer fitted with the whisk attachment.
  • Add the chocolate and butter mixture into the eggs. Use a spatula for this. Add the 1 tsp vanilla extract and mix.
  • Next add in the 1/2 cup flour, 1/4 cup cocoa powder, and 1/2 tsp kosher salt. Mix gently until combined.
  • Pour the batter into the prepared pan and bake for 26-28 minutes.
  • Remove the brownies from the oven and add 2 cups of mini marshmallows on top.
  • Either return the brownies to the oven for 3 minutes (be careful not to burn the marshmallows!) or torch the marshmallows with a kitchen torch– my preferred way!
  • Make the brownie frosting. In a large bowl melt the butter 30 seconds at a time in the microwave until fully melted.
  • Add in the ⅓ cup cocoa powder and whisk until smooth.
  • Add in the 2 cups of confectioners sugar and 3 tbsp milk.
  • Immediately spread on top of the marshmallows and let set. The frosting will harden quickly so don’t wait to slather it on top!

Notes

If you don’t have a kitchen torch, let the brownies bake in the oven for 3-5 minutes making sure they don’t burn.
Serving: 1brownie, Calories: 300kcal, Carbohydrates: 43g, Protein: 3g, Fat: 14g, Saturated Fat: 8g, Polyunsaturated Fat: 1g, Monounsaturated Fat: 4g, Trans Fat: 0.4g, Cholesterol: 55mg, Sodium: 139mg, Potassium: 132mg, Fiber: 2g, Sugar: 35g, Vitamin A: 320IU, Calcium: 22mg, Iron: 1mg
Did you make this recipe?Please leave a star rating and review in the form below. I read them all!

I love when you share my recipes!!