From my favorite baking book: Baking IllustratedGerman Chocolate Layer Cake with Coconut-Pecan Filling
German Chocolate Cake:
1 1/4 cups unbleached all-purpose flour, plus more for dusting the pans
1/4 cup non-alkalized cocoa, such as Hershey's
2 tsp. instant espresso or coffee powder
1/3 cup boiling water
1/3 cup buttermilk or plain yogurt
2 tsp. vanilla extract
12 tablespoons unsalted butter, softened but still cool
1 1/4 cups sugar
3 large eggs, at room temperature
1/2 tsp. baking soda
1/2 tsp. salt
Coconut-Pecan Filling
4 large egg yolks
1 cup sugar
1/4 tsp. salt
8 tablespoons unsalted butter, softened but still cool
1 cup heavy cream
1 tsp. vanilla extract
1 1/2 cups chopped pecans, toasted
2 cups lightly packed sweetened flaked coconut
1. For the cake: Adjust an oven rack to the middle position and heat the oven to 350 degrees. Generously grease two 8-inch round cake pans and cover the pan bottoms with rounds of parchment paper or waxed paper. Grease the parchment rounds and dust the pans with flour, tapping out the excess.
2. Mix the cocoa and instant espresso powder in a small bowl; add th boiling water and mix until smooth. Cool to room temperature, then stir in the buttermilk and vanilla.
3. Beat the butter in the bowl of a standing mixer at medium-high speed until smooth and shiny, about 30 seconds. Gradually sprinkle in the sugar; beat until the mixture is fluffy and almost white, 3-5 minutes. Add the eggs 1 at a time, beating 1 full minute after each addition.
4. Whisk the flour, baking soda, and salt in a medium bowl. With the mixer at the lowest speed, add about a third of the dry ingredients to the batter, followed immediately by about a third of the cocoa mixture; mix until the ingredients are almost incorporated into the batter. Repeat the process twice more. When the batter appears blended, stop the mixer and scrape the sides of the bowl with a rubber spatula. Return the mixer to low speed; beat until the batter looks satiny, about 15 seconds longer.
5. Divide the batter evenly between the pans. With a rubber spatula, spread the batter into the pan sides and smooth the tops. Bake the cakes until they feel firm in the center when lightly pressed and a toothpick or thin skewer comes out clean or with just a crumb or two adhering, 23-30 minutes. Transfer the pans to wire racks; cool for 10 minutes. Run a knife around the perimeter of each pan, invert the cakes onto the racks, and peel off the paper liners. Re-invert the cakes onto additional racks; cool completely before frosting.
6. For the filling: Mix the egg yolks, sugar and salt in a medium bowl; beat in the butter, then gradually beat the cream and vanilla into the mixture. Pour into a medium, non-reactive saucepan and cook over low heat, stirring constantly, until the mixture is puffy and just begins to thicken and the temperature reaches 180 degrees on an instant-read thermometer, 15-20 minutes. Pour the mixture into a medium bowl and cool to room temperature. Stir in pecans and coconut.
7. To assemble: Use a long serrated knife to cut the cakes in half horizontally so that each cake forms 2 layers. Place 1 of the cake bottoms on a serving plate. Spread about 1 cup filling over the cake half. Place another halved cake round over the filling. Repeat this stacking an spreading process with the remaining filling and cake, ending with a final layer of the filling.
This cake was easier than it sounds and really good. The filling is way better than what you can find ready-made. I omitted the espresso powder altogether. I also found that the filling took longer than 20 minutes on low heat, so I'd heat it up a little more and keep an eye on it. Seriously, really good and worth a try.
