These fudgy marshmallow brownies combine a chocolate brownie with marshmallow fluff. These brownies are ultra fudgy and full of chocolate chips. There is marshmallow fluff swirled in the brownie batter before it bakes.
These gooey marshmallow brownies are like s'mores brownies except without the graham crackers. They are incredibly fluffy and have a marshmallow fluff swirl!
These fudgy brownies are super rich and sweet, but if you add them with a glass of milk or a scoop of vanilla ice cream, they are perfect!
Why This Marshmallow Brownie Recipe Works
- Fudgy texture- These brownies are fudgy and have pockets of chocolate chips through out. The brownie recipe is based off my Better Than Boxed Brownies.
- Chocolate brownies- These brownies are incredible and both cocoa powder and chocolate chips.
- Marshmallow fluff- The marshmallows make these brownies taste even fluffier!
- Chocolate lovers- If you love chocolate, you will love these brownies.
Step By Step Recipe Video
Ingredient Notes for Marshmallow Brownies
Here are some notes on the ingredients. For a full list of ingredients, check out the recipe card below.
- Eggs+ Egg yolk- I used the large eggs cold. The extra egg yolk helps with the fudgy texture.
- Unsalted butter- The butter gets melted and cooled before using.
- Oil- You can use canola oil, vegetable oil, or olive oil.
- Unsweetened cocoa powder- For best results, use dutch-process cocoa powder for a more rich brownie. This is the one I used.
- Cornstarch- This helps to break down the gluten to form a more fudgy texture.
- Chocolate chips- Use semisweet chocolate chips or dark chocolate chips. I don't recommend milk chocolate chips because it will be too sweet.
- Marshmallow crème or marshmallow fluff- You can use either of these. Different parts of the country, it is called one of those.
- Dairy free- You can use your favorite dairy free options for this recipe!
- Gluten free- I haven't tested this gluten free. Let me know if you do.
Step By Step Instructions- Brownie Batter
Here is how to make and bake these fudge brownies. This recipe uses a 9X9-inch square baking pan, a stand mixer with a whisk attachment or a hand mixer (electric mixer), and a rubber spatula.
STEP 1: Mix the dry ingredients. Use a sifter, to sift the all-purpose flour, cocoa powder, and cornstarch into a medium bowl. Then, add in the salt.
STEP 2: Beat the sugar and eggs. Using a mixer in a large bowl, beat the sugar, eggs, and egg yolk on high speed for 5 minutes. It will start off as yellow, then turn into a white pale color. This is how the brownies will get their crackle top. It also helps the brownies rise.
STEP 3: Add wet ingredients. Next, add the melted butter, oil, and vanilla extract and mix on low speed.
STEP 4: Add flour mixture. Add this into the sugar mixture and mix on low speed until just combined. Then, fold in the chocolate chips.
STEP 5: Swirl the batter. Pour the brownie batter into the prepared pan. Then, place melted marshmallow fluff dollops on top of the brownies. Use a knife to swirl it in.
STEP 6: Bake. Bake the marshmallow swirl brownies for 45-55 minutes.
Next, cool the gooey chocolate brownies on a cooling rack completely.
Expert Baking Tips
- Flour- Make sure the flour is spooned and leveled. If you stick the measuring cup directly into the flour, it will compact the flour. Compacted flour can cause the brownies to be cakey.
- The brownies should be slightly underdone, because they will continue to cook as they cool. If they are overbaked, they will lose their fudgy texture.
- To easily remove the brownies, spray the pan with baking nonstick spray. Line the bottom of the pan and 2 sides with parchment paper and spray again. Once they are done cooling, you can easily remove from the pan.
- To get a perfect cut, use a sharp knife and cut the brownies. Wipe the knife after each cut. Also, place the brownies in the freezer for 10 minutes before cutting.
This is because they were underbaked. They probably needed 5-10 more minutes in the oven.
You can use 8X8-inch baking pan to make thicker brownies. You can double the recipe to use a 9X13-inch baking pan. Half the recipe to use a loaf pan.
You can place the marshmallow swirl on top of the brownie batter is down baking and then broil the top.
- 9X9 pan: I use metal square pans for baking. I don't recommend glass pans.
- Parchment paper: I use premade sheets of parchment paper vs the roll of parchment paper. It makes baking a lot easier!
- Baking spray: I use the nonstick spray that has flour in it.
- Offset spatula: I use
Storing and Freezing
Store the marshmallow brownies in an airtight container at room temperature. Store up to 5 days.
You can heat them in the microwave until warm and serve with vanilla ice cream.
You can freeze the marshmallow brownies in individual squares. Store in an airtight container and freeze up to 30 days.
To thaw, either let it come to room temperature, or heat in the microwave until warm.
Other Brownie Recipes To Try
Try These Marshmallow Recipes
- 2 cups White granulated sugar
- 3 Large eggs
- 1 Egg yplk
- ½ cup Unsalted butter melted
- 2 teaspoon Pure vanilla extract
- ½ cup Oil canola or vegetable
- ¾ cup All-purpose flour
- 1 cup Unsweetened cocoa powder Use dutch process cocoa powder
- 1 ½ tablespoon Cornstarch
- ½ teaspoon Salt
- 1 cup Semi-sweet chocolate chips
- 1 cup Marshmallow creme
- Preheat the oven to 325°F. Spray a 9X9-inch baking pan with baking nonstick spray. Line the bottom and 2 sides of the pan with parchment paper and spray again.
- In a medium bowl, sift the flour, cocoa powder, and cornstarch together. Add in the salt and set aside.¾ cup All-purpose flour, 1 cup Unsweetened cocoa powder, 1 ½ tablespoon Cornstarch, ½ teaspoon Salt
- Using a mixer with a whisk attachment, beat the sugar, eggs, and egg yolk on high speed for 5 minutes. It will become pale in color. While that mixes, melt the butter in the microwave and let it cool.2 cups White granulated sugar, 3 Large eggs, 1 Egg yplk, ½ cup Unsalted butter
- Add the oil, melted butter, and vanilla and mix on low until combined. Add in the dry ingredients and mix on low until just combined. Pour in the chocolate chips and use a rubber spatula to fold it in.2 teaspoon Pure vanilla extract, ½ cup Oil, 1 cup Semi-sweet chocolate chips
- Pour the brownie batter into the pan. Melt the marshmallow fluff in the microwave for 20-30 seconds and mix. Use a 1 teaspoon to dollop the marshmallow fluff on top of the brownie batter. Use a butter knife to very light swirl the marshmallow fluff.1 cup Marshmallow creme
- Bake for 45-55 minutes. It is done baking when you stick in a toothpick, and it is slightly wet. If a lot of batter comes out, then bake for another 5 minutes.
- Cool on a cooling rack completely before cutting into them and serving.