Chocolate Mousse Cake

Directions

1. 1
   Lightly coat the insides of 3 x 9 x 1 1/2-inch cake pans with melted butter.
2. 2
   Line each pan with parchment paper, then lightly coat the parchment paper with more melted butter.
3. 3
   Set aside.
4. 4
   Preheat the oven to 325F (160C)ahrenheit.
5. 5
   Heat 1 inch of water in the bottom half of a double boiler over medium heat.
6. 6
   Place remaining butter and 8 ounces semisweet chocolate in the top half of the double boiler.
7. 7
   Tightly cover the top with film wrap.
8. 8
   Allow to heat for 10 to 12 minutes.
9. 9
   Remove from the heat, stir until smooth, and hold at room temperature.
10. 10
    Place the egg yolks and 3/4 cup sugar in the bowl of an electric mixer fitted with a paddle.
11. 11
    Beat on high until slightly thickened and lemon-colored, about 4 minutes.
12. 12
    Scrape down the sides of the bowl and beat on high for an additional 2 minutes.
13. 13
    While the egg yolks are beating, whisk 4 egg whites in a large stainless steel bowl until stiff, but not dry, about 3 to 4 minutes.
14. 14
    Using a rubber spatula, fold the melted chocolate mixture into the beaten egg yolk mixture.
15. 15
    Add a quarter of the beaten egg whites and stir to incorporate, then gently fold in the remaining egg whites.
16. 16
    Divide the batter between the prepared pans, spreading evenly, and bake in the preheated oven until a toothpick inserted in the center comes out clean, about 25 to 30 minutes.
17. 17
    Remove the cakes from the oven and allow to cool in the pans for 15 minutes.
18. 18
    (During baking, the surface of the cakes will form a crust; this crust will normally collapse when the cakes are removed from the oven.)
19. 19
    Invert the cakes onto cake circles, remove the parchment paper, and refrigerate for 30 minutes.