Chocolate Mousse Brownies Heaven

A decadent combination of rich, fudgy brownies layered with silky, airy chocolate mousse. I love how the dense brownie base contrasts with the light mousse topping, creating a bite that’s indulgent yet perfectly balanced.

Why You’ll Love This Recipe

I find these brownies to be the ultimate treat for chocolate lovers like me. The brownie layer gives a satisfying chew, while the mousse melts effortlessly on the tongue. They’re elegant enough for a dinner party, yet simple enough for a weekend baking project.

Ingredients

(Here’s a tip: Check out the full list of ingredients and measurements in the recipe card below.)

Brownie Layer

• 1 cup (2 sticks) unsalted butter

• 2 cups granulated sugar

• 4 large eggs

• 1 teaspoon vanilla extract

• 1 cup all-purpose flour

• ¾ cup unsweetened cocoa powder

• ½ teaspoon baking powder

• ¼ teaspoon salt

Chocolate Mousse Layer

• 1 cup heavy cream, chilled

• 1 cup semisweet or bittersweet chocolate chips (about 6 oz), melted and slightly cooled

• 2 tablespoons powdered sugar

Directions

1. I preheat my oven to 350°F (175°C) and grease or line a 9×9-inch baking pan.

2. In a heat-proof bowl over simmering water, I melt the butter, then remove it from the heat and whisk in the sugar until smooth. I beat in the eggs one at a time and stir in the vanilla.

3. I whisk together the flour, cocoa powder, baking powder, and salt, then fold it gently into the butter mixture until just combined.

4. I pour the batter into the prepared pan and bake for 25–30 minutes, until a toothpick inserted in the center comes out with a few moist crumbs. I make sure not to overbake so the brownies stay fudgy. I let them cool completely in the pan.

5. While the brownies cool, I whip the chilled cream and powdered sugar to soft peaks, then fold in the melted chocolate until smooth and airy.

6. I spread the mousse evenly over the cooled brownies and chill them for at least 2 hours, until the mousse is set.

7. I slice them into squares and serve chilled or at cool room temperature.

Servings and timing

Servings: 9 squares
Prep Time: 15 minutes
Bake Time: 25–30 minutes
Chill Time: 2 hours
Total Time: about 2 hours 45 minutes
Calories: around 360 kcal per serving

Variations

When I want extra texture, I stir chopped toasted nuts into the brownie batter. For a more intense chocolate hit, I use dark chocolate in the mousse layer. A dash of espresso powder in the brownie batter also deepens the chocolate flavor beautifully.

Storage/Reheating

I keep these brownies in an airtight container in the fridge for up to 5 days. I don’t reheat them, but I sometimes let them sit out for 10–15 minutes before serving so the mousse softens slightly.

FAQs

Can I freeze these brownies?

Yes, I wrap them tightly in plastic wrap and store them in the freezer for up to 2 months. I thaw them in the fridge overnight before serving.

Can I use boxed brownie mix?

Yes, I can prepare my favorite brownie mix as the base, then follow the mousse instructions.

Can I make the mousse with milk chocolate?

Yes, but I reduce the powdered sugar slightly to keep it from becoming overly sweet.

How do I get clean slices?

I use a sharp knife dipped in hot water and wiped clean between each cut.

Can I make these dairy-free?

Yes, I use vegan butter for the brownies and whip coconut cream for the mousse, pairing it with dairy-free chocolate.

Conclusion

I love how these chocolate mousse brownies combine two desserts into one indulgent square. They’re rich, elegant, and sure to impress anyone who takes a bite, making them perfect for celebrations or just satisfying a serious chocolate craving.

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