Cup of Yum
1. Preheat oven to 350°F / 180°C. Line the bottom of three 8 inch cake pans with parchment paper, and butter and dust the sides with cocoa powder. Set aside until needed.

Cocoa mixture

1. Place the hot coffee, cocoa powder and chocolate in a small saucepan. Heat this mixture while stirring to melt the chocolate and cocoa powder in the coffee. Once you have a smooth mixture and all the chocolate is melted, remove the saucepan from the heat. It does not need to come to a boil.
2. Add the salt, sour cream and vanilla and whisk them in until smooth. Set aside until needed.

Devil’s food cake batter

1. Place the softened butter and white sugar in the mixing bowl of your stand mixer. With the paddle attachment, cream the butter and sugar together until you have a light, fluffy, creamy butter-sugar mix. This can take a few minutes on medium high speed, depending on how cold the butter was at the beginning. Remember to scrape down the sides of the bowl to ensure all the butter is mixing well.
2. Add the eggs, one at a time, at medium speed. Add the next egg as soon as the previous one is mixed through. Don’t over-beat the eggs (approximately 30 seconds per egg). Scrape down the sides of the bowl half way through.
3. Once the eggs are added, add the cocoa mixture. Scrape the sides and bottom of the bowl.
4. In a separate bowl, sift the flour and baking soda together. Add this to the batter in 2 - 3 additions and fold the flour into the wet ingredients. Do not over-mix. Only mix until the flour is mixed in and there are no lumps.
5. Divide the batter between the prepared cake pans. You can either measure this by weight, or use an ice cream scoop or measuring cup to divide the batter evenly.
6. Tap the cake pan against the countertop 2 - 3 times to remove any air bubbles and to evenly distribute the batter.
7. Bake in the preheated oven for 25 - 35 minutes. The cake is done when a clean toothpick inserted into the middle of the cake comes out clean. The cake will also pull slightly away from the sides of the pan.
8. Remove the cake pans from the oven and let them sit for about 5 minutes to cool down slightly. Then turn them out onto a cooling wire rack to cool completely.

Frosting

1. While the cake is baking. make chocolate Swiss meringue buttercream according to the recipe here, with the ingredient amounts listed above. This will be more than enough to generously fill and frost the cake and to decorate.
2. To go with the easier option, you can make 3 batches of this simple American chocolate buttercream instead.

Filling and frosting the cake

1. Place a cake board on a decorating stand (or plate). Place a little buttercream on the cake board, and then place a cake layer on top of that. This buttercream will help secure the bottom cake layer to the board.
2. Add about 1 cup of frosting (or as much or as little as you want) and spread it evenly on the surface of the cake layer. Place the second layer on top of that. Repeat with the same amount of frosting.
3. Place the third layer on top (with the flat side facing up). Apply a thin layer of frosting to cover the whole cake. This thin layer is the crumb coating.
4. Place the cake in the fridge or in a cool place in your house for a few minutes, to help set the crumb coating.
5. Once the crumb coating is set, apply a generous layer of frosting. Create swirls for a rustic look, or use a frosting scraper to create smooth sides. Use a spatula to make the frosting on top smooth as well.
6. Pipe a frosting border along the edge of the cake on top (optional). The cake is now ready to be served.