Ingredients
Cake
- 2 cups sugar
- 1-3/4 cups all-purpose flour
- 3/4 cup cocoa powder
- 1 1/2 tsp baking powder
- 1 1/2 tsp baking soda
- 1 teaspoon salt
- 2 eggs
- 1 cup milk
- 1/2 cup vegetable oil
- 2 tsp vanilla extract
- 1 cup boiling water
Heat oven to 350°F. Grease 10″ and baking pans or two 8″ pans.
Stir together sugar, flour, cocoa, baking powder, baking soda and salt in large bowl. Add eggs, milk, oil and vanilla and beat on medium speed for about 2 minutes. Stir in the boiling water (your batter will be very thin–that’s OK!). Pour batter into cake pans.
Bake on the high rack for about 40 minutes for if you make one large cake and 30-35 minutes for the two smaller cakes or until a toothpick inserted in the center comes out clean. Allow to cool in the pan for 10 minutes; remove from pans to wire racks. Cool completely.
Once cakes have cooled, use a sharp serrated knife to torte and cut cake evenly twice, horizontally, so that you end up with three thin cake layers. Or cut each of the 8″inch cakes in half to get four layer and a higher cake.
Place your first cake layer on your cake serving plate. Spread a big dollop of mousse filling on top of that cake layer. Repeat with the remaining cake layers, adding a layer of mousse filling between each layer of cake.
Take any remaining mousse filling and spread it evenly around the entire outside and top of the cake. Refrigerate for 20-30 minutes.
Chocolate Mousse Filling:
- 6 oz. bittersweet chocolate (preferably 70% cacao), chopped (about 1 cup)
- 5 1/4 oz (10 1/2 Tbs.) unsalted butter
- 3 large eggs, separated
- 1 1/2 Tbs. granulated sugar
- 1 1/8 cup heavy cream
- 1/3 tsp. pure vanilla extract
- Pinch kosher salt
Melt the chocolate and butter in a large bowl set in a skillet of barely simmering water. Remove from the heat and stir with a spatula to combine. Set aside to cool slightly.
Whip the egg whites in a clean stand mixer fitted with a clean whisk attachment on medium-high speed to soft peaks, 1 to 2 minutes. Slowly add the sugar and continue to whip to stiff peaks, 3 to 4 minutes.
In a medium bowl, whip the cream with a whisk or electric hand mixer to medium-stiff peaks.
In a small bowl, combine the egg yolks, vanilla, and salt. Mix the egg yolk mixture into the chocolate mixture with a spatula. Fold in the whipped egg whites, then fold in the whipped cream—there shouldn’t be any visible streaks.