Decadent chocolate mousse brownie recipe! These chewy/fudgy brownies are topped with an easy homemade chocolate mousse for the ultimate chocolate dessert.
This Chocolate Mousse Brownie recipe is a seriously chocolaty dessert! The brownies are rich and fudgy and chewy. They make the perfect base for the light and fluffy chocolate mousse.
The brownies are also a great make-ahead option. They taste just as good, maybe even a little better, the second day.
So, treat yourself, or a loved one, to some chocolaty goodness with these Chocolate Mousse Brownies (or take it a step farther and try my French Silk Brownies)!
“We ate the whole pan of brownies in one sitting. They were amazing, couldn’t eat just one. :)” – Diane
Ingredient notes and substitutions
- Butter: I use salted butter. If you use unsalted butter, increase the salt to 3/4 teaspoon.
- Flour: It’s key to properly measure the flour. Using too much flour will give you cakier brownies. To properly measure it, either weigh it (click on “metric” just above the ingredients) or sift or stir it to break it up, lightly spoon it into a measuring cup, and level.
- Cocoa powder: I use unsweetened cocoa powder (like Hershey’s, Trader Joe’s, or Ghirardelli) in this recipe. Different brands of cocoa powder will give you lighter or darker chocolate mousse.
- Milk: You can use any milk from skim milk to whole milk.
- Whipped cream: If you need some extra tips and pointers on how to make whipped cream, this post has that info.
How to make chocolate mousse brownies
Here you’ll find step-by-step photos showing how to make this recipe. The full recipe, including ingredients, is given below.
Step 1: Melt butter in a saucepan.
Step 2: Mix in sugar.
Step 3: Remove from heat and stir in vanilla.
Step 4: Mix in eggs.
Step 5: Mix in flour, cocoa powder, and salt just until combined. Don’t overmix.
Step 6: Pour the batter into pan.
Step 7: Bake until a toothpick inserted into the center of the brownies comes out with a few fudgy crumbs.
Step 8: To make the chocolate mousse, add the chocolate, marshmallows, and milk to a saucepan.
Step 9: Heat until melted and well-combined. Set aside to cool.
Step 10: Whip the heavy cream.
Step 11: Fold in the cooled chocolate mixture into the whipped cream.
Step 12: Spread the chocolate mousse over the cooled brownies.
Recipe Tips!
- Brownie making tips: If you want a more in-depth guide to making brownies, check out this post for more tips.
- Checking for doneness: Brownies are different because you want a few fudgy crumbs when checking for doneness. If the toothpick comes out with no crumbs, the brownies are overcooked. If there’s batter, keep baking.
- No leavening?: I get questions from time to time about the lack of leavening agents in brownies. Brownies don’t typically have a leavening agent because brownies are meant to be rich and dense, not light and fluffy.
- Garnish: I like to grate a bit of semisweet chocolate over the top of the brownies before serving.
Storage
These brownies should be stored in an airtight container in the refrigerator. They will keep for up to 4 days when properly stored in the fridge.
More chocolate mousse dessert recipes!
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Chocolate Mousse Brownie Recipe
Ingredients
Brownies
- ¾ cup butter
- 1 ½ cups granulated sugar
- 1 tablespoon vanilla extract
- 2 large eggs
- ¾ cup all-purpose flour properly measured
- ½ cup unsweetened cocoa powder
- ½ teaspoon salt
Chocolate Mousse
- ¾ cup miniature marshmallows
- 4 ounces semi-sweet baking chocolate chopped
- ¼ cup milk
- 1 cup cold heavy whipping cream
Instructions
Brownies
- Preheat oven to 350 F. Grease or use parchment paper to line a 9×9-inch baking pan.
- In a large saucepan, melt butter.¾ cup butter
- Turn heat to low, and stir in sugar. Let cook, stirring constantly, for 2-3 minutes.1 ½ cups granulated sugar
- Remove from heat, and stir in vanilla.1 tablespoon vanilla extract
- Let mixture cool for about 5 minutes.
- Whisk in eggs until combined.2 large eggs
- Add flour, cocoa powder, and salt. Whisk in until just incorporated.¾ cup all-purpose flour, ½ cup unsweetened cocoa powder, ½ teaspoon salt
- Pour batter into prepared pan, spreading batter as needed.
- Bake for 20-30 minutes. The edges should look done, but the center should still look shiny. A toothpick inserted in the center should come out with a few fudgy crumbs.
- Cool completely.
- To make the mousse, heat marshmallows, chocolate, and milk in a medium saucepan over low heat, stirring constantly until completely smooth.¾ cup miniature marshmallows, 4 ounces semi-sweet baking chocolate, ¼ cup milk
- Cool completely.
Chocolate Mousse
- In a separate bowl, beat whipping cream to stiff beats.1 cup cold heavy whipping cream
- Fold in cooled chocolate mixture.
- Spread mousse evenly over brownies.
- Chill brownies for at least 30 minutes, or until ready to serve.
- Cover and chill leftover brownies.
Notes
- Butter: I use salted butter. If you use unsalted butter, increase the salt to 3/4 teaspoon.
- Flour: It’s key to properly measure the flour. Using too much flour will give you cakier brownies. To properly measure it, either weigh it (click on “metric” just above the ingredients) or sift or stir it to break it up, lightly spoon it into a measuring cup, and level.
- Cocoa powder: I use unsweetened cocoa powder (like Hershey’s, Trader Joe’s, or Ghirardelli) in this recipe. Different brands of cocoa powder will give you lighter or darker chocolate mousse.
- Milk: You can use any milk from skim milk to whole milk.
- Whipped cream: If you need some extra tips and pointers on how to make whipped cream, this post has that info.
- Nutrition values are estimates.
Nutrition
Did You Make This Recipe?
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Originally published February 12, 2016. This post is regularly updated.
Slightly adapted from Let’s Dish Recipes.
Reader Interactions
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Comments & Reviews
Diane says
We ate the whole pan of brownies in one sitting. They were amazing, couldn’t eat just one. :)
Tricia says
Scrumptious! We all loved them.
Kate says
Thank you so much! I’m so glad to hear that!
Julia says
I love the layers! With this I don’t have to choose between fluffy mousse and dense brownie!
Kate says
Thanks so much, Julia!! It’s always nice when you don’t have to choose between desserts! =D
grace says
twd ftw! :)
the brownies are awesome too. :)
Kate says
Thanks so much! Can’t wait to watch it tomorrow! =D