Line a conventional size cupcake pan with paper liners.
Sift together the dry ingredients: 1 pound 4oz cake flour, 6oz cocoa powder, 0.8oz baking powder, 0.2oz baking soda, and 3oz buttermilk powder.
In a stand mixer fitted with the whip attachment, whisk together 1 pound whole eggs and 1 pound 9oz granulated sugar until light and fluffy. Slowly drizzle in 12oz oil while mixer is running. Stir in 1 pound 3oz water, 0.5oz vanilla, and 0.5oz coffee flavor. Add the sifted dry ingredients and mix until just together, scrape the bowl, and mix on 2nd speed for 30 seconds.
Use a #16 blue scoop to deposit 2oz batter into each cavity. Bake at 350F until cupcakes spring back lightly when touched. Let cool completely and depan.
Combine 8oz butter, 13oz brown sugar, 4oz egg yolks, and 1 pound evaporated milk in a medium saucepan over medium heat. Whisk occasionally as the mixture comes to a low boil. Once boiling, whisk constantly until the mixture thickens, about 5 minutes. Remove from heat and stir in 0.5oz vanilla, 0.1oz salt, 10oz toasted pecans, and 10oz coconut. Allow to cool completely before using.
Using a #40 purple scoop, scoop 1oz prepared German Chocolate Icing. Place fudge icing in a piping bag fitted with a medium star tip and pipe around edges of cupcakes.