Cake: Cake: For a 3-layer cake, place on baking rack one-third from the bottom of the oven and the second two-thirds from the bottom. Preheat the oven to 350° degrees. Line the bottom of three 9-inch or two 10-inch pans with parchment paper rounds, grease with butter, and dust with flour. Combine the butter, water, and vegetable oil in a medium saucepan set over medium heat. In a large bowl, stir together the sugar, cocoa, and flour. Pour the butter mixture into the sugar mixture and whisk until smooth. Whisk in the eggs, one at a time; then whisk in the buttermilk. Whisk in the baking soda, salt, and vanilla all at once. Transfer the batter to the prepared pans. For a 3-layer cake, stagger the cake layers on the oven racks so that no layer is directly over another. Set two layers on one rack and third on the other. For a 2-layer cake, stagger the layers on the middle rack with one placed more toward the front of the oven and one toward the back. Bake for 35 to 40 minutes, or until a toothpick inserted in the middle of each layer comes out clean. Monitor the layers carefully for doneness; each one may be done at different times. Remove the cakes from the oven and cool on racks for about 15 minutes before inverting onto baking racks. Cool the cakes completely, at least 2 hours, before frosting. Frosting: Using a mixer fitted with a whisk attachment, whip the cream in a large bowl on high speed until soft peaks form. Add the powdered sugar and whip until thoroughly combined. Place one cake layer on a platter and spread some of the frosting over the top. Top with the remaining layers, thickly coating the top and sides of teach with frosting. Refrigerate the cake until the whipped cream frosting has stabilized, at least 1 hour. Glaze: Place the chocolate in a medium bowl. Heat the cream in a small saucepan over medium heat until it is very hot and just beginning to steam. Pour the hot cream over the chocolate and stir until it has melted completely. Stir in the syrup and vanilla. Pour the glaze into a medium pitcher or measuring cup and let cool for 10 minutes. Do not let the glaze sit longer because it will stiffen and become difficult to pour over the cake. Slowly pour the glaze over the cake, ensuring that it covers the top of the cake entirely, but make sure some of the cream frosting show through the drizzles on the sides. Add more corn syrup to the glaze if necessary to make it flow better. Refrigerate the cake until the glaze is set and the whipped cream frosting is firm, at least 1 hour. Slice the cake with a long serrated knife, dipping it into a tall glass of hot water between each slice. Yield: 12 to 14 servings. Tip: Whipped cream usually begins to separate shortly after it has been beaten. The secret to this frosting—and its stability—is the powdered sugar. Powdered sugar has added cornstarch, which stabilizes the cream. |