Introduction

Indulge in the rich decadence of Chocolate Mousse Brownies, a layered dessert combining a fudgy brownie base with airy chocolate mousse and a glossy ganache topping. This recipe is perfect for chocolate lovers looking to impress with a homemade treat that’s both elegant and satisfying.

A square dark brown chocolate cake sits in a silver baking pan on a white marbled surface. On top of the cake, there are 10 thick, smooth dollops of light brown chocolate frosting, each shaped like a swirl with a glossy texture. To the top right of the pan, there is a clear glass bowl filled with more light brown chocolate frosting, showing a smooth, soft texture. Below and to the right of the baking pan, a spatula with a light wooden handle and dark gray blade has small smears of chocolate frosting on it. A white cloth is partially visible beneath the bottom left corner of the pan. photo taken with an iphone --ar 4:5 --v 7

Ingredients

1/2 cup (115g) unsalted butter, melted
1 cup (200g) granulated sugar
2 large eggs
1 tsp vanilla extract
1/3 cup (40g) unsweetened cocoa powder
1/2 cup (65g) all-purpose flour
1/4 tsp salt
1/4 tsp baking powder
1 1/2 cups (350ml) heavy whipping cream, chilled
8 oz (225g) semisweet chocolate, finely chopped
3 tbsp (45ml) milk
2 tbsp (25g) powdered sugar
4 oz (115g) semisweet chocolate, finely chopped (for ganache)
1/2 cup (120ml) heavy cream (for ganache)

Instructions

Step 1: Preheat the oven to 350°F (175°C) and line an 8×8-inch (20×20 cm) square baking pan with parchment paper, leaving a slight overhang for easy removal.
Step 2: In a large bowl, whisk together the melted butter, sugar, eggs, and vanilla extract until smooth and well combined.
Step 3: Sift in the cocoa powder, flour, salt, and baking powder. Gently fold these dry ingredients into the wet mixture until no streaks remain. Avoid overmixing.
Step 4: Pour the batter into the prepared pan and smooth the top. Bake for 20 to 25 minutes until a toothpick inserted comes out with a few moist crumbs. Let cool completely in the pan.
Step 5: Heat the milk in a small saucepan over low heat until steaming. Pour over the chopped chocolate in a heatproof bowl. Let sit 2 minutes, then stir until smooth. Cool to room temperature.
Step 6: In a separate bowl, beat the chilled heavy cream and powdered sugar until soft peaks form.
Step 7: Stir a spoonful of whipped cream into the cooled chocolate mixture to loosen it. Gently fold in the remaining whipped cream until blended and airy, being careful not to deflate it.
Step 8: Spread the chocolate mousse evenly over the cooled brownie base. Refrigerate for at least 2 hours until set.
Step 9: For the ganache, place chopped chocolate in a heatproof bowl. Heat heavy cream until it simmers, pour over chocolate, and let sit 2–3 minutes. Stir until smooth and glossy.
Step 10: Pour ganache over the chilled mousse layer and smooth the surface. Return to refrigerator for 1 hour until firm.
Step 11: Lift the dessert from the pan using parchment overhang. Slice with a clean, sharp knife, wiping between cuts for neat edges. Serve and enjoy!

Tips & Variations

Use high-quality semisweet chocolate for the mousse and ganache to deepen the chocolate flavor.
For a nutty twist, sprinkle chopped toasted hazelnuts or walnuts over the mousse layer before adding ganache.
Ensure the heavy cream is well chilled before whipping to achieve the best volume and texture.
Do not overbake the brownie base; it should remain moist to complement the light mousse layer.

Storage

Store the mousse brownies in an airtight container in the refrigerator for up to 3 days. To serve, allow them to sit at room temperature for 10–15 minutes to soften slightly. Avoid freezing as it may change the mousse texture.

How to Serve

A square chocolate brownie sits inside a metal baking pan with a thick layer of creamy chocolate frosting spread on top in large round dollops, creating an uneven textured surface with swirls and peaks. Next to the pan is a glass bowl filled with smooth chocolate frosting, showing a swirl pattern, and a spatula with a wooden handle covered in some frosting lying flat on the white marbled surface. A white cloth is partially tucked underneath the pan at the bottom left corner. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I make these brownies ahead of time?

Yes, you can prepare the entire dessert a day in advance. Just keep it refrigerated and covered to maintain freshness and texture.

What can I substitute for heavy cream in the mousse?

For the mousse, heavy cream is best for whipping and texture. If unavailable, you might try full-fat coconut cream as a dairy-free alternative, but flavor and consistency may vary.