Pre-heat oven to 350 F. Prepare two 8-in cake pans, oiling sides of pan and dusting them with cocoa powder. Then trace the outlines of the cake pan over parchment paper forming a circle, cut and place at the bottom of the pan. Set aside
In a medium-sized bowl mix flour, baking powder, baking soda, salt and black cocoa powder with an electric mixer, beat sugar and butter for 1 minute on medium-high speed. Mixture should resemble light wet sand. Add eggs, one at a time
Start adding flour mixture, alternating with milk, and beat on medium speed until fully combined. Beat for 1 more minute. Add vanilla extract and coffee and mix until just combined.
Distribute batter evenly in both cake pans and bake for 30-35 minutes, or until a toothpick inserted in the middle comes out with just a few crumbs. Let sit on the pan for 15 minutes, then remove from pan and place on a wire rack to cool completely
Beat butter until creamy in medium- high speed, about 1 1/2 minutes. Add powdered sugar, cocoa powder, heavy cream, salt and vanilla extract. Beat on low until just incorporated, then beat in medium-high speed for 2 minutes, until light and fluffy
Level your cake layers with a serrated knife or with a leveler, removing cake domes until the top of the cake is flat. Place the first layer of cake on your cake plate, centered, and using an ice cream scoop, add 3 scoops of frosting on top, distribute evenly and place the second cake layer on top.
Add a very thin coat on top and sides of the cake -the crumb coat- that will help "glue" the crumbs and seal the cake's moisture. Refrigerate for 10 minutes. Add the rest of your frosting, making swirls with the back of a spoon or with an angled spatula. Add any sprinkle or decoration you want.