Ingredients

  • 2 ounces Bakers Germans Sweet Chocolate, coarsely chopped
  • 1 cup all-purpose flour
  • 1/3 cup Dutch-process cocoa powder
  • 1/4 teaspoon baking soda
  • 1/4 teaspoon fine salt
  • 8 tablespoons unsalted butter (1 stick), at room temperature, plus more for coating the baking dish
  • 1 cup granulated sugar
  • 2 large eggs, at room temperature
  • 1 large egg yolk, at room temperature
  • 1 teaspoon vanilla extract
  • 1/2 cup low-fat buttermilk, at room temperature
  • 3/4 cup heavy cream
  • 1/2 cup granulated sugar
  • 2 large egg yolks
  • 1 1/4 cups unsweetened coconut flakes, toasted and crumbled
  • 3/4 cup pecans, toasted and finely chopped
  • 3 tablespoons unsalted butter, cut into small pieces
  • 1/4 teaspoon fine salt
  • Vanilla Buttercream Frosting, at room temperature (see Game Plan note)

Method

  • Heat the oven to 350 degrees F and arrange a rack in the middle.
  • Coat a 13-by-9-inch baking dish with butter; set aside.
  • Fill a small saucepan with 1 inch of water and bring it to a simmer over medium-high heat.
  • Place the chocolate in a stainless steel or glass bowl, set the bowl over the simmering water (be sure its not touching the water), and stir until the chocolate is completely melted, about 3 to 5 minutes; set aside to cool slightly.
  • Combine the flour, cocoa powder, baking soda, and salt in a large bowl and whisk to aerate and break up any lumps; set aside.
  • In the bowl of a stand mixer fitted with a paddle attachment, cream the measured butter and sugar on medium-high speed until light in color and fluffy, about 4 minutes.
  • Add the eggs, 1 at a time, then the egg yolk, beating after each addition until evenly incorporated.
  • Stop the mixer and scrape down the sides of the bowl using a rubber spatula.
  • Add the vanilla and melted chocolate and return the mixer to medium-high speed, mixing until evenly combined, about 30 seconds.
  • Reduce the speed to medium low and add a third of the reserved dry ingredients.
  • When just incorporated, add half of the buttermilk.
  • Repeat, scraping down the bowl at least once and ending with the last third of the dry ingredients.
  • Pour the batter into the prepared dish, smooth the top with the spatula, and bake until a toothpick inserted in the middle comes out with only a few crumbs, about 35 minutes.
  • Cool completely in the pan on a wire rack, about 1 hour.
  • Meanwhile make the filling.
  • Combine the cream, sugar, and egg yolks in a medium saucepan over medium heat, stirring constantly until the mixture thickens and coats the back of the spoon, about 8 minutes.
  • Transfer to a medium bowl, add the remaining ingredients, and stir until the butter has melted and is evenly incorporated.
  • Let cool to room temperature.
  • Once the cake has cooled, carefully transfer it to a cutting board and slice it into thirds (the pieces should measure about 4 inches wide by 9 inches long), trimming as necessary to make the sections as even as possible.
  • Spread about a third of the filling evenly over the top of 1 piece of cake, and another third of the filling over the top of a second piece.
  • Stack the 2 pieces and place the last, unadorned piece on top.
  • Set the last third of the filling aside.
  • Using about a third of the vanilla buttercream, frost the sides and top of the cake.
  • (Dont worry about looks at this pointthis is just a base coat, or crumb layer, and it will be covered up later.)
  • Place the cake in the freezer for about 10 minutes, or the refrigerator for about 20 minutes, until the frosting is set up and slightly hard.
  • Evenly spread the remaining frosting over the top and sides of the cake, then evenly spread the remaining third of the filling on top of the cake.