German Chocolate Cake

FOR CAKE: Preheat the oven to 350 degrees F. Butter an 8-by-2-inch round cake pan and line the bottom with parchment paper. In a bowl, sift together the sugar, flour, cocoa, baking soda, baking powder, and salt. In another bowl, whisk together the eggs, coffee, buttermilk, and vanilla. Beat the coffee mixture into the dry ingredients in 2 batches with an electric mixer on low speed. Beat in the butter. Pour the batter into the prepared pan and bake for about 50 minutes, or until a cake tester inserted in the center comes out clean. Let the cake cool in the pan on a rack. FOR GANACHE: In a small saucepan, bring the cream to a boil over moderately high heat. Remove from the heat and stir in the chocolate. Let stand for 1 minute, then whisk until smooth. Transfer the ganache to a bowl and refrigerate, stirring occasionally, until chilled and thickened, about 2 hours. FOR FILLING: In a heavy medium saucepan, whisk together the egg yolks and sugar. Whisk in the evaporated milk and then the butter. Cook over moderate heat, stirring constantly, until the mixture thickens and lightly coats a spoon, about 10 minutes; do not let it boil. Remove from the heat and stir in the coconut, pecans, and vanilla. Transfer to a bowl and let cool completely. TO SERVE: Invert the cake onto a work surface and peel off the paper. Using a serrated knife, slice the cake horizontally into 3 even layers. Set a layer on a large plate and spread on half of the nut filling. Top with the second cake layer and cover with a 1/4-inch-thick layer of ganache. Set the third cake layer on top and cover with the remaining nut filling. Spread half of the remaining ganache on the sides. Transfer the rest of the ganache to a pastry bag fitted with a medium star tip. Pipe a border of rosettes around the top of the cake and serve. MAKE AHEAD: The recipe can be prepared through Step 4 one day ahead. Let the cake stand at room temperature; refrigerate the ganache and nut filling separately. If the cold ganache is too thick to spread, stir it briefly.