Chocolate Mousse Cake

Lightly coat the insides of three 3 x 9 x 1 1/2-inch cake pans with
melted butter. Line each pan with parchment paper, then lightly coat
the parchment paper with more melted butter. Set aside.

Preheat the oven to 325 degrees Fahrenheit.

Heat 1 inch of water in the bottom half of a double boiler over medium
heat. Place remaining butter and 8 ounces semisweet chocolate in the
top half of the double boiler. Tightly cover the top with film wrap.
Allow to heat for 10 to 12 minutes. remove from the heat, stir until
smooth, and hold at room temperature.

Place the egg yolks and 3/4 cup sugar in the bowl of an electric mixer
fitted with a paddle. Beat on high until slightly thickened and
lemon-colored, about 4 minutes. Scrape down the sides of the bowl and
beat on high for an additional 2 minutes.

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.

Using a rubber spatula, fold the melted chocolate mixture into the
beaten egg yolk mixture. Add a quarter of the beaten egg whites and
stir to incorporate, then gently fold in the remaining egg whites.

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. Remove the cakes from the
oven and allow to cool in the pans for 15 minutes. (During baking,
the surface of the cakes will form a crust; this crust will normally
collapse when the cakes are removed from the oven.) Invert the cakes
onto cake circles, remove the parchment paper, and refrigerate for 30
minutes.