My Sister's Chocolate Mousse Cake
December 31, 2017
“My sister's chocolate mousse cake, vanilla sponge cake with cherry and raspberry filling”
My sister's chocolate mousse cake, a birthday cake on a white stand: a smooth, tall band of chocolate mousse over vanilla sponge with cherry and raspberry filling, a piped border of cream at the base and a pile of fresh strawberries, cherries and raspberries on top.
A mousse cake is assembled in a ring or springform. The sponge goes in the bottom, the fruit filling is spread short of the edge so it stays hidden, and the mousse is poured over to fill the mold and set. When you lift the ring the sides are perfectly straight, as they are here. Cherry with chocolate borrows from the Black Forest tradition.
This article is written in Corey’s voice for this tribute site, based on his captions and blog. His own words are the quotes above.
Chocolate Mousse Cake with Raspberry Filling
A ring-molded mousse cake is the workhorse of the French pastry shop: a sponge base, a bright fruit layer and a tall band of chocolate mousse set without baking. The mousse here is made on a pâte à bombe, egg yolks cooked with hot sugar syrup, which gives a rich, stable foam that slices cleanly. Use vanilla sponge for contrast or chocolate sponge for depth.
Ingredients
Vanilla sponge (or chocolate variation)
- 3 large eggs (150 g), at room temperature
- 90 g granulated sugar (scant 1/2 cup)
- 90 g all-purpose flour (3/4 cup), or 70 g flour plus 20 g cocoa powder for chocolate
- 20 g unsalted butter, melted (1 1/2 Tbsp)
- 1 tsp vanilla extract
Raspberry filling
- 250 g raspberries, fresh or frozen (2 cups)
- 50 g granulated sugar (1/4 cup)
- 10 g lemon juice (2 tsp)
- 4 g powdered gelatin (1 1/4 tsp), soaked in 20 g cold water
Chocolate mousse
- 280 g dark chocolate, 60 to 66% cacao, chopped
- 100 g egg yolks (5 large)
- 100 g granulated sugar (1/2 cup)
- 35 g water (2 Tbsp plus 1 tsp)
- 500 g heavy cream, 35% fat, cold (2 cups plus 2 Tbsp)
To finish
- Cocoa powder for dusting, or 100 g dark chocolate shaved into curls
- 125 g fresh raspberries (1 cup)
Method
- Heat the oven to 350°F (175°C). Whip the eggs and sugar over simmering water to 40°C (104°F), then off the heat until thick and tripled. Fold in the sifted flour, then the butter and vanilla, and bake in a parchment-lined 8-inch (20 cm) round pan for 20-25 minutes. Cool completely and slice a level layer about 1/2 inch (1.2 cm) thick.
- For the filling, simmer the raspberries, sugar and lemon juice for 5 minutes until the fruit breaks down. Strain out the seeds if you like, stir in the soaked gelatin, and cool until thick but still spreadable.
- Line an 8-inch (20 cm) ring, 2 1/2 inches (6 cm) tall, with acetate and set it on a board. Trim the sponge to 7 inches (18 cm), center it in the ring, and spread the raspberry filling over it, stopping short of the edge. Chill while you make the mousse.
- Melt the chocolate to 45-50°C (113-122°F) and keep it warm. Whip the cream to soft peaks and refrigerate.
- Start the yolks whipping in a stand mixer. Boil the sugar and water to 118°C (244°F) and pour it in a thin stream down the side of the bowl with the mixer on medium, then whip on high until the pâte à bombe is pale, thick and cooled to room temperature.
- Whisk a third of the whipped cream into the warm chocolate until smooth and glossy. Fold in the pâte à bombe, then the remaining cream, stopping as soon as the color is even.
- Pour the mousse into the ring, letting it flow down between the sponge and the acetate so the side of the finished cake is pure mousse. Smooth the top and refrigerate at least 6 hours or overnight.
- Lift off the ring and peel away the acetate. Dust with cocoa or cover with chocolate curls, crown with fresh raspberries, and serve chilled but not ice cold.
Chef’s notes
- If the chocolate seizes into flecks when the cream goes in, it was too cool or the cream too cold. Have the chocolate at 45-50°C (113-122°F) and whisk the first third of cream in fast.
- Syrup that hits the whisk spins into hard threads on the bowl. Pour between the whisk and the wall of the bowl in a steady stream.
- Overwhipped cream makes a heavy, buttery mousse. Stop when the cream just holds a soft, drooping peak, because folding finishes the job.
- The cake can be frozen in its ring for up to 2 weeks. Thaw overnight in the refrigerator and decorate just before serving.
Classic French mousse or sabayon style?
Sabayon or pâte à bombe mousse
Pierre Hermé, Ferrandi Paris and most professional pastry kitchens
Egg yolks are cooked by a 118°C (244°F) sugar syrup, whipped to a foam, and folded into melted chocolate with whipped cream. The yolks are heat treated, the texture is creamy and stable enough to stand in a ring, and it freezes well. This recipe follows this method.
Classic French mousse with egg whites
Julia Child, Elizabeth David and traditional bistro kitchens
Yolks are stirred into melted chocolate and the mixture is lightened with whipped raw egg whites, often with no cream at all. The flavor is the most intensely chocolate and the texture the airiest, but the eggs are uncooked and the foam is too fragile to slice as a cake.
Drawn from the methods of
- Pierre Hermé and Dorie Greenspan, Chocolate Desserts by Pierre Hermé (2001)
- Ferrandi Paris, French Pâtisserie (2017)
- Julia Child, Louisette Bertholle and Simone Beck, Mastering the Art of French Cooking (1961)
- Bo Friberg, The Professional Pastry Chef (2002)
Corey has not published his own formula for this piece. This reference recipe is compiled from the published methods of the chefs and bakers listed above, written in our own words.
