Easy Marshmallow Brownies

Chewy brownies with soft, sweet marshmallows topped with a rich chocolate, peanut butter layer with crispy rice cereal makes amazing Marshmallow Brownies!

This combination of chocolate and mini-marshmallows make an irresistible sweet treat.

If you like this brownie recipe you may also enjoy Texas Brownies, Chocolate Syrup Brownies, Triple Layer Brownies, and our Big Batch of Brownies.

Marshmallow Brownies Recipe

These brownies are perfect dessert for birthday parties, Valentine’s Day, potlucks, carry-in meals or when you want show somebody they are special. I love that you can use a board scraper or butter knife to cut them into 1” squares or bigger pieces like you’d get a sweet shop.

Start with a family size brownie box mix, then top with marshmallows for a fun twist on a classic dessert recipes. The real magic is in the sweet and crunchy topping. Add a mixture of melted semi-sweet chocolate chips, peanut butter and Rice Krispie cereal.

Chill and the layers in these beautiful brownies slice up so nicely to make the best marshmallow brownies recipe!

Everyone I’ve seen eat these Brownies with gooey marshmallows enjoys them.

Ingredients Needed:

• Box of family size brownie mix
• Vegetable oil
• Water
• Eggs
• Mini marshmallows
• Semi-sweet chocolate chips
• Peanut butter
• Butter
• Rice Krispie cereal

How to Make Marshmallow Brownies

1. Preheat oven to 350 degrees F and grease bottom of 13 x 9-inch pan.
2. Prepare and bake brownies following package directions for original recipe.
3. Sprinkle marshmallows on hot brownies.  Bake for 3 minutes longer.
4. Combine chocolate chips, peanut butter and butter in a medium saucepan.  Cook on low heat stirring constantly until chips are melted.
5. Add rice cereal and mix well.
6. Spread mixture over marshmallow layer.
7. Refrigerate until chilled.  Cut into bars and enjoy!

Step By Step Instructions

Mix up a box of your favorite brand of a family size brownie mix and bake until a toothpick comes out clean.

Take care not to over stir or over bake.

Then sprinkle a bag of mini marshmallows evenly over the top.

Bake for 3 minutes until marshmallows look a bit melty.

Allow pan to cool for at least 20 – 30 minutes. The pan will cool faster when removed from the top of the hot oven.

To make the scotcheroo style topping combine chocolate chips, peanut butter and butter in a microwave safe baking dish.

Stir every 30 seconds. I like to use a silicone spatula.

Or cook on low heat in a medium saucepan stirring constantly until chips are melted. 

Add rice cereal and mix well. 

Spread mixture over marshmallow layer.

Spooning works best, but pouring is an option if you’re in a hurry and are a less detail oriented person.

Some of the marshmallows rise up through the topping making random patterns or swirls in the topping that tastes so yummy!

Refrigerate until chilled. Then cut and serve.

Store covered in an airtight container in a cool place.

Recipe Tips & Tricks

• Use fresh marshmallows for best results.
• Can spread a layer of marshmallow creme over baked brownies and bake for 2 minutes as a substitute.
• Allow marshmallow layer to cool before adding melted chocolate on top or the marshmallows will deflate quite a bit.
• Spoon Chocolate over the top for more even distribution than pouring.
• Take care not to burn the brownies – we have a convection oven and that can make brownies, cakes, and cookies bake more quickly.
• Should the Gooey Marshmallow Brownies get transported or covered with an airtight lid before cooling, the marshmallows will bubble up through the top chocolate layer and give the dessert a marbled look.  If you take plenty of time and allow everything to cool and release steam and keep the dish level the top layer will remain an even layer of chocolate.

How to Keep Brownies From Falling Apart

Gooey Marshmallow Brownies slice easiest when chilled and using a serrated knife or a board scraper.  As the brownies get to room temperature they are more likely to crumble and begin to fall apart.

We like this recipe chilled and we like how it gets gooier as it warms up.  The perfect example of a winning recipe is that it tastes good in any situation!

I have an assistant that was cheering wildly for this recipe during our photo session.  She has taught me to take pictures faster because she loves sampling everything chocolate!  Her hands kept edging closer to the pan as she was saying “Chocolate.  Chocolate. Chocolate.”  Before she even tasted the recipe she knew how to describe it 🙂

Other rich desserts in a 13 x 9-inch pan that our family enjoys

• The Best Moist & Rich Chocolate Cake
• The Best Cake Recipe
• Cinnamon Applesauce Cake
• Smores Cake
• Chocolate Covered Strawberry Cake
• Easy Triple Chocolate Fudge Cake

Printable Gooey Marshmallow Brownies Recipe

Originally shared April 18, 2019 with pictures updated on January 31, 2023.