Step 1

Preheat the oven to 350, and place an oven rack in the center position of the oven.

Step 2

Spray one 6" cake pan with 2" sides with cooking spray, and then line the bottom with a circle of parchment paper and spray again.

Step 3

In a large bowl, whisk together the flour, sugar, cocoa powder, baking soda and salt.

Step 4

In a large measuring cup, whisk together the oil, vanilla, vinegar, and coffee.

Step 5

Slowly pour the coffee mixture into the bowl while whisking. Whisk until the cake batter is mostly lump-free, but try not to mix too much and make a dense cake batter.

Step 6

Scrape the batter into the prepared cake pan, and bake on the center rack of the oven for 32-34 minutes, until a toothpick inserted into the cake comes out clean.

Step 7

While the cake cools, make the frosting: beat together the softened 'butter' with the powdered sugar, cocoa powder, vanilla, pinch of salt and 1 tablespoon of coffee. Add the remaining coffee if needed to bring it together.

Step 8

Once the cake is cool, slice it in half horizontally. Place the bottom of the cake on a plate, and scoop 1/3 of the frosting on top. Spread the frosting almost to the edges. Place the remaining cake layer on top, and frost with the remaining frosting. If desired, portion some frosting into a bag fitted with an open star tip and decorate the cake with buttercream roses and sprinkles.