I wanted to make something extra special for Valentine’s Day, not really because of the holiday itself but more because I’ll take any excuse I can to make something I wouldn’t normally make. Such was the case with this cake. Chocolate mousse is one of my favorite desserts, so this cake was a no-brainer for me. Plus, Valentine’s seemed like an appropriate time to make something consisting of three layers of chocolate. Since I’m pregnant, I figure it’s okay to tell you that I licked the whisks and spatulas several times while preparing this (for those I’m sharing it with – don’t worry, I washed them each time). :)
This cake, upon first glance, seems incredibly involved. When you break down each step, though, it’s really not that difficult. The most annoying part for me was having to wash my stand mixer’s bowl between steps. This dessert starts out with a flourless chocolate cake base. Next comes a layer of chocolate mousse, followed by a layer of white chocolate mousse. The texture of this cake is unbeatable. You’ve got an incredible combination of rich, dense cake, light and airy mousse layers and a crisp bite from the chocolate curls. This cake is the epitome of decadence. It was a struggle not to eat the entire piece when I was done photographing it. If you’re looking to make something special for your valentine, look no further.
One thing I didn’t do that I wish I had done was to dip the knife in hot water before slicing this. I was so excited and didn’t think about it until it was too late. I definitely recommend using that method if you don’t have any cheese wire to use. Your slices will come out looking much neater and smoother if you cut with a hot knife.
Triple Chocolate Mousse Cake
Serves 12 to 16
Ingredients:
For the bottom layer:
6 tablespoons unsalted butter, cut into six pieces
7 ounces bittersweet chocolate, chopped fine
3/4 teaspoon instant espresso powder
4 large eggs, separated
1 1/2 teaspoons vanilla extract
Pinch cream of tartar
Pinch salt
1/3 cup packed light brown sugar
For the middle layer:
5 tablespoons hot water
2 tablespoons cocoa powder
7 ounces bittersweet chocolate, chopped fine
1 1/2 cups heavy cream, chilled
1 tablespoon granulated sugar
1/8 teaspoon salt
For the top layer:
3/4 teaspoon powdered gelatin
1 tablespoon water
6 ounces white chocolate chips
1 1/2 cups heavy cream, chilled
Shaved chocolate or cocoa powder for decorating, optional
To prepare the bottom layer, preheat oven to 325º. Grease a 9- or 9 1/2-inch springform pan. Combine butter, chocolate and espresso in a large heatproof bowl set over a pan of barely simmering water. Stir occasionally until melted and smooth. Remove from heat and allow to cool slightly, about 5 minutes. Whisk in egg yolks and vanilla and set aside.
Using a stand mixer fitted with the whisk attachment, whip egg whites, cream of tartar and salt on medium-low speed until foamy, about 1 minute. Add half of sugar and continue whipping until combined, about 15 seconds. Add remaining sugar, increase speed to high, and whip until soft peaks form, 1 additional minute, scraping down bowl halfway through. Using a whisk, fold one-third of the egg whites into the chocolate mixture to lighten it. Fold in remaining egg whites using a rubber spatula. When no white streaks remain, carefully transfer batter to prepared pan. Smooth top with spatula. Bake cake until it has risen, is firm around the edges and just set in the center (cake center should spring back when gently pressed with finger), 13 to 18 minutes. Transfer to a wire rack to cool completely, about 1 hour. Do not remove cake from pan.
While cake is cooling, prepare middle layer. Combine the hot water and cocoa in a small bowl and set aside. Place chocolate in a large heatproof bowl set over a pan of barely simmering water. Stir occasionally until melted and smooth. Remove from heat and allow to cool slightly, 2 to 5 minutes.
Using a stand mixer fitted with the whisk attachment, whip cream, sugar and salt on medium-low speed until foamy, about 1 minute. Increase speed to high and whip until soft peaks form, 1-3 minutes. (It helps to chill the mixing bowl before whipping the cream.) Whisk cocoa mixture into chocolate. Using a whisk, fold one-third of the cream into the chocolate mixture to lighten it. Fold in remaining cream using a rubber spatula. When no white streaks remain, spoon mousse onto cooled cake. Smooth top with spatula and gently tap on counter to release any air bubbles. Wipe inside edge of pan with a damp cloth or paper towel to remove any drips. Refrigerate for at least 15 minutes while preparing top layer.
To prepare the top layer, sprinkle gelatin over water and let sit for at least 5 minutes. Place white chocolate in a medium heatproof bowl. Bring 1/2 cup of cream to a simmer in a small saucepan over medium-high heat. Remove from heat and stir in gelatin mixture until completely dissolved. Pour cream mixture over white chocolate, cover and allow to sit for 5 minutes. Whisk gently until smooth. Let cool to room temperature, stirring occasionally (mixture will thicken slightly during this time).
Using a stand mixer fitted with the whisk attachment, whip remaining cup of cream on medium-low speed until foamy, about 1 minute. Increase speed to high and whip until soft peaks form, 1 to 3 minutes. Using a whisk, fold one-third of cream into white chocolate to lighten it. Fold in remaining cream using a rubber spatula. When no white streaks remain, spoon white chocolate mousse into the pan over the middle layer. Smooth top with a rubber spatula. Return to refrigerator and chill until set, at least 2 1/2 hours. Cake can be refrigerated up to 1 day. Allow to sit at room temperature for about 45 minutes before slicing.
To serve, garnish cake with chocolate curls or dust with cocoa if desired. Run a thin knife between the cake and sides of pan. Remove sides and run the cleaned knife along the outside to smooth. Cut using cheese wire or a hot knife, cleaning and drying between each cut.
Source: The Cook’s Illustrated Cookbook
