Swiss Truffle Cake

Makes two 5 by 9 in cakes (12 servings). In a medium saucepan, bring the cream, butter, and corn syrup to a boil over moderate heat. Remove from the heat, add the chocolate, stir once and let stand for 5 minutes. Whisk until smooth and strain into a bowl. Refrigerate until thickened, about 2 hours. Preheat the oven 350 and position a rack in the middle. Butter a 10 1/2 by 15 1/2 " jelly roll pan and line the bottom with parchment paper. Butter the paper. In a small bowl set over a saucepan of hot water, melt the chocolate, stirring occasionally. Let cool. In a large bowl, using an electric mixer, cream the butter with half of the sugar. Beat in the chocolate; then beat in the egg yolks 1 at a time. Combine the almonds and bread crumbs and stir them into the batter. In large bowl, whip the egg whites until they hold very soft peaks. Gradually beat in the remaining sugar until the whites hold firm peaks. Stir one-quarter of the whites into batter, then fold in the remaining whites. Spread the batter evenly in the prepared pan. Bake for 20 min. Let the cake cool in the pan for 2 min, then loosen the sides with tip of a knife. Invert the cake onto a rack and peel off the paper. Cover the cake with another rack and turn it right side up. Let cool to room temperature. To assemble the 2 cakes, halve layer crosswise. Cut each half crosswise into thirds, each about 3 1/2 by 7 3/4 ". Cut 2 pieces of stiff cardboard about 1/4 " larger than the layers. Place 1 cake rectangle on each cardboard. Gently whisk the ganache to a spreading consistency. Using a long metal spatula, spread each of the 2 rectangles of cake with about 3 T of ganache. Cover with 2 more layers of cake and ganache. Frost the sides of 2 cakes with ganache. To finish, spoon the remaining ganache into a pastry bag fitted with a 1/2 " plain tip and pipe thick diagonal strips on top of the cakes. Refrigerate the cakes to set, about 2 hours. Let the cakes return to room temperature. Just before serving, dust the tops of the cakes with cocoa powder.