Chocolate Mousse Cake~

Adapted from Cook's Illustrated

12 tablespoons (1 1/2 sticks) unsalted butter, cut into 12 pieces, plus softened butter for greasing pan
Flour for dusting pan
12 ounces semisweet chocolate, chopped
1 ounce unsweetened chocolate, chopped

1 teaspoon vanilla extract
1 tablespoon Kahlua
8 large eggs, separated
1/8 teaspoon salt 

2/3 cup brown sugar

Preheat oven to 325º. Butter then flour sides of 9-inch springform pan. Line bottom of pan with parchment round. Wrap bottom and sides of pan with large sheet of foil.

Melt 12 tablespoons butter and chocolates in large bowl and microwave for 30 second increments, stirring occasionally, until chocolate mixture is smooth. Cool mixture slightly, then whisk in vanilla, Kahlua and egg yolks. Set chocolate mixture aside.

In a standing mixer fitted with whisk attachment, beat egg whites and salt at medium speed until foamy, then add half of the brown sugar, beat at high speed until combined, then add remaining brown sugar and continue to beat at high speed until soft peaks form, about 2 minutes longer. Using whisk, stir about a third of beaten egg whites into chocolate mixture to lighten it, then fold in remaining egg whites in 2 additions with a spatula. Pour batter into prepared springform pan, then set springform pan in large roasting pan. Carefully fill the roasting pan with hot water to a depth of 1 inch. Bake until cake has risen, is firm around edges, center has just set, and instant-read thermometer inserted into center registers about 170º, 45 to 55 minutes.

Remove springform pan from water bath, discard foil, and cool on wire rack 10 minutes. Run a knife between sides of pan and cake to loosen, then cool cake in springform pan until barely warm, about 3 hours. Wrap pan in plastic wrap and refrigerate until thoroughly chilled, at least 8 hours or up to 2 days.

To serve cake, remove sides of pan. Slide thin metal spatula between cake and pan bottom to loosen, then invert cake onto large plate, peel off parchment, and re-invert onto serving platter. To cut, dip a knife in hot water...and wipe between each cut. Serve with berries and sweetened whipped cream.

Serves 12-16