4oz(113g)black cocoa powderwe used Guittard 100% Cocoa Noir
2 tsp(2 1/2tsp)baking powder
8ounces(227g)unsalted butterroom temperature
24ounces(680g)sifted powdered sugar
2Tablespoonclear vanilla extract
4Tablespoonsmilk or water
Stand mixer with paddle attachment
For the cake
NOTE: If you use a cocoa powder that is different than listed, your cake will not be as dark. You can supplement the color with 1 tsp of super black food coloring
Adjust an oven rack to the middle position and preheat to 350ºF/176ºC.
Grease three 8" cake pans with cake goop.
Whisk together melted chocolate, cocoa powder, hot coffee, vanilla, and oil until combined (it will look lumpy). Then mix in the warm buttermilk and whisk until combined. Then set aside.
Add butter to stand mixer and beat at medium-high speed until smooth and shiny, about 30 seconds. Gradually sprinkle in the sugar, beat until mixture is fluffy and almost white, about 3-5 minutes. Add the eggs 1 at a time, mixing in fully before adding the next egg.
Whisk the flour, baking powder, baking soda, and salt in a medium bowl.
With the mixer at the lowest speed, add about a third of the dry ingredients to the batter, followed immediately by about a third of the chocolate mixture, mix until ingredients are almost incorporated into the batter. Repeat the process 2 more times. When the batter appears blended, stop the mixer and scrape the sides of the bowl with a rubber spatula. Return the mixer to low speed, beat until the batter looks like satin, about 15 seconds longer.
Divide the batter evenly between the prepared pans. Smooth the tops with a rubber spatula. Bake cakes until they feel firm in the center and a toothpick comes out clean or with just a few crumbs on it, about 30-35 minutes.Transfer pans to a wire rack and let cool for 10 minutes. Invert cakes onto the rack and pop cakes out of pans. Cool completely before frosting.
Sweet Buttercream Frosting
Cream your butter until smooth with the whisk attachment (by hand or in the stand mixer is fine)
Add the vegetable shortening to the butter and cream until smooth
While mixing on low, start adding in your powdered sugar one cup at a time until it's all combined with the butter mixture
Add in your salt, vanilla and milk and whip on medium for 10-15 minutes until very light and fluffy
If your frosting is too thick, you can add in 1-2 more Tablespoons of water or milk to thin it down to your desired consistency.
You can now add in your desired food coloring if you prefer your frosting to be colored. I used electric pink, electric green and electric pink food coloring from americolor.com. Remember, the frosting color will deepen after 24 hours.
If you can't find black cocoa powder you can use regular dutch cocoa powder plus 1 teaspoon of black food coloring or 2 Tablespoons activated charcoal mixed in with your liquid ingredients before adding it to your batter.