Preheat oven to 350°F.
Grease three 6x2-inch round or two 9x2-inch round cake pans with cake goop or cooking spray and line the bottoms with parchment paper. Whisk together 1 cup brewed black coffee, ¾ cup cocoa powder, and 2 tablespoons malted milk powder until smooth. Set aside.
Combine 2 cups granulated sugar, 1¾ cup cake flour, 1½ tablespoons King Arthur Cake Enhancer, 1¾ teaspoon baking soda, 1 teaspoon baking powder, and 1 teaspoon salt in a large bowl or stand mixer fitted with a whisk attachment.
Beat in 3 large eggs, 1 cup buttermilk, ½ cup canola oil, and 1 teaspoon vanilla extract until fully incorporated, then beat at medium speed for 2 minutes, the batter is going to be very thin.
Pour 2 cups of batter into each 6-inch pan (480g of batter per pan) or divide evenly between the two 9-inch pans (about 720g of batter per pan).
Bake 6-inch cakes for 30 to 35 minutes and 9-inch cakes for 40 to 45 minutes until a toothpick or cake tester comes clean from the center.
Cool in pans for at least 10 minutes and loosen from sides of pan before transferring to a cooling rack to cool completely.
Prepare the frosting according to the recipe directions. Frost the cooled cake, starting with a crumb coat and chilling for 30 minutes before adding the final coating.
Add chocolate sprinkles for the final touch.