Le Gateau Victoire au Chocolat Mousseline

Heat oven to 350 degrees F/ 180 Centigrade. Place rack in lower third level. Prepare a 10 cup (2 1/2 l) cake pan by buttering and flouring it. Choose a roasting pan larger than the cake pan, fill it half way with hot water, place roasting pan in oven. Mix coffee and hot water in a medium-size saucepan, add rum and chocolate (broken up). Melt chocolate mix over boiling water in another sauce pan. Break eggs into a bowl, add sugar. Hold this bowl over hot water while stirring for two minutes (or until eggs feel slightly warm). Beat eggs for 5 minutes or until mixture has tribpled in volume. Pour cream into a metal mixing bowl. Set cream (in bowl) in another bowl filled with ice and water. Whip until cream has doubled in volume. Then whip in vanilla. Pull melted chocolate from stove. Beat it with a wire wisk, it should be smooth. Mix chocolate into the eggs, blending rapidly with a rubber spatula. Then fold in whipped cream. Turn batter into cake pan. Put cake pan into pan of hot water in the oven. Bake for 1 hour. Cake is done when a skewer comes out clean (cake will rise 1/8 inch 1/2 cm above edge of pan). Leave cake in oven, turn off heat, open door. Let cake sit in water for 30 minutes. (It will sink) remove from oven, keep it in the water. Let it sit another 30 minutes. Unmold the cake and sprinkle with confectioner's sugar.