Bittersweet Chocolate Mousse Brownies

Rich, velvety bittersweet chocolate and airy whipped cream come together in perfect harmony in these decadent brownies.

With a dense, fudgy base and a light-as-air mousse topping, these indulgent treats will satisfy any chocolate craving and leave you weak in the knees.

Ready Time

2 hrs 15 mins

Yields

8 servings

Ingredients

For the brownies:
1 1/2 sticks unsalted butter, plus more for greasing the pan
1 cup unsweetened cocoa powder
3/4 cup granulated sugar
1/2 cup brown sugar
4 large eggs
2 teaspoons pure vanilla extract
1 3/4 cups all-purpose flour
1 teaspoon salt
For the chocolate mousse:
8 ounces high-quality bittersweet chocolate, broken into small pieces
1 cup heavy cream, chilled
2 large egg whites
2 tablespoons granulated sugar
1/2 teaspoon pure vanilla extract
Pinch of salt

Instructions

Preheat your oven to 350°F (175°C).

Grease an 8-inch square baking pan with butter and line it with parchment paper, leaving some overhang for easy removal.

Melt the butter and cocoa powder in a medium saucepan over low heat, whisking constantly, until smooth.

Remove from heat and stir in granulated sugar, brown sugar, and vanilla extract until combined.

Let cool slightly.

Beat in the eggs one at a time, followed by the flour and salt.

Pour the batter into the prepared pan and smooth the top.

Bake for 25-30 minutes or until a toothpick inserted 2 inches from the edge comes out with a few moist crumbs.

Let cool completely in the pan.

For the chocolate mousse, melt the chocolate in a double boiler or in the microwave in 30-second increments, stirring between each interval until smooth.

Let cool slightly.

In a separate bowl, whip the heavy cream until stiff peaks form.

In another bowl, whisk together the egg whites, granulated sugar, and vanilla extract until stiff peaks form.

Fold the egg mixture into the whipped cream until no streaks remain.

Fold the cooled chocolate into the whipped cream mixture until combined.

Stir in a pinch of salt.

Cut the cooled brownie into 8 squares.

Spoon a layer of chocolate mousse on top of each brownie square.

Refrigerate for at least 30 minutes to set before serving.

Notes

To ensure the brownies are fudgy and not cakey, don’t overbake them – a few moist crumbs on the toothpick are okay! Use high-quality bittersweet chocolate for the best flavor in the mousse.

If you want a lighter mousse, you can add a bit more heavy cream.

Don’t skip letting the brownies cool completely in the pan – it’ll make them easier to cut and handle.

Keep the chocolate mousse refrigerated until serving, as it’s best when chilled and set.

You can also make the mousse ahead of time, but wait to assemble the brownies until just before serving.