Easy Chocolate Mousse Cake with Granola Brownie Base

June 25, 2026Jakie Bowles

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Best Cake Delicious Easy To Make Fruit Granola Handmade No Preservatives Recipe Whole Grain Oats

A showstopper for summer! Beautiful layers of chocolate and cream top a chewy granola brownie for a dessert that feels both elegant and effortless. Cool, creamy and rich with chocolate, it's the perfect treat to serve on a warm summer evening.

While this layered dessert looks bakery-worthy, it comes together surprisingly quickly. The granola brownie base is simple and straightforward, while the light chocolate mousse and fluffy whipped cream whip easily into irresistible layers of creamy, chocolatey goodness.

Thank you to one of our favorite Rainbow Trout Kitchen fans, Ann, for this photo holding her raspberry topped creation - a fabulous Chocolate Mousse Cake!

Ingredients

You'll need a springform pan and parchment paper.

Brownie

Softened butter to grease the springform pan

1 cup RTK classic almond granola, crunched up

3/4 cup Dutch-processed cocoa powder

6 Tbsp all-purpose flour

1/2 tsp salt

1 1/3 cup light brown sugar

1/2 cup melted butter

1 1/2 tsp vanilla extract (we only use Madagascar)

2 large eggs

Chocolate Mousse

1/3 cup hot tap water

3 Tbsp Dutch-processed cocoa powder

8 oz semisweet chocolate, chopped

1 3/4 cup heavy cream

1/4 tsp salt

1 tsp vanilla extract

1 1/2 cup raspberries

Whipped Cream

1 1/2 cup heavy cream

1 1/2 tsp vanilla extract

2 Tbsp confectioners' sugar

Raspberries for serving, cocoa powder for dusting (optional)

Instructions

1. Prep: Preheat the oven to 325 degrees. Grease the bottom of a springform pan (at least 3 inches high). Cut parchment into a circle to line the bottom, and cut a strip to line the sides.

2. Make the Brownie Layer: In a small bowl whisk cocoa, flour, salt and crushed up granola.

3. In a large bowl, whisk brown sugar, melted butter & vanilla. Add in eggs. Fold dry ingredients in with a spatula just until flour disappears. Do not over mix.

4. Pour the batter into the prepared springform pan. Bake for 35 minutes, rotating the pan at the halfway point. You'll know it's ready when a cake tester comes out with a few moist crumbs.

5. Let the brownie cool in the pan on a rack - or in the refrigerator - until it's room temperature.

6. Make the Mousse! Once the brownie has cooled, you can make the mousse. Whisk the hot tap water and cocoa in a small bowl. Melt the chocolate in a glass dish in the microwave.

7. Using a mixer, beat the cream, salt & vanilla on medium-high speed until the cream thickens, but does not hold peaks. When you lift the whisk, the cream should form ribbons as it falls.

8. Stir the cocoa mixture into the chocolate with a spatula. Gently fold the cream until a few streaks remain, then fold in the raspberries. Spread the mousse evenly onto the cooled brownie. Transfer to the refrigerator.

9. Make the Whipped Cream: With the mixer, whisk the cream, vanilla & sugar on medium-high speed until stiff peaks form. Spread the cream over the mousse layer.

Refrigerate for at least 2 hours and up to 24 hours. If refrigerating overnight, loosely cover with plastic wrap.

To serve, pop open the springform pan and transfer your beautiful cake to a platter. Garnish with fresh raspberries and a sprinkle of cocoa powder on top!

Ingredients

Instructions

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