• Preheat your oven to 350°F.
• Grease and flour two 9-inch round cake pans.
• In a large bowl, whisk together the flour, sugar, cocoa, baking powder, baking soda, and salt.
• Add the buttermilk, vegetable oil, eggs, and vanilla extract to the bowl with the dry ingredients, and mix until well combined.
• Add in the boiling water, and mix until smooth.
• Divide the batter evenly between the two prepared cake pans.
• Bake for 30-35 minutes, or until a toothpick inserted in the center of the cake comes out clean.
• Allow the cakes to cool in the pans for about 10 minutes, then transfer them to a wire rack to cool completely.

To make the frosting:

• In a medium-sized saucepan, combine the sweetened condensed milk, evaporated milk, egg yolks, and butter.
• Cook over low heat, stirring constantly, until the mixture has thickened and is bubbly.
• Remove from heat, and stir in the vanilla extract, coconut, and pecans.
• Allow the frosting to cool to room temperature, stirring occasionally.

To assemble the cake:

• Place one of the cake layers on a cake stand or serving plate.
• Spread about 1/3 of the frosting over the top of the cake.
• Place the second cake layer on top of the frosting, and spread the remaining frosting over the top of the cake.
• Store the cake in the refrigerator for at least 30 minutes to set the frosting.
• Enjoy your delicious German Chocolate Cake!