Devil's food cake with chocolate buttercream

Heat the oven to 350F. Butter and flour two nine inch cake pans and line each with a parchment round.

Sift the flour, salt, baking soda and baking powder together into a large bowl and whisk.

Whisk the Dutch processed cocoa powder with the vegetable oil into a smooth black slurry.

Cream the room temperature butter with a paddle attachment until smooth, then beat in the cocoa slurry.

Add the light brown sugar and the granulated sugar and mix about five minutes until light and fluffy, scraping the bowl down.

Add the room temperature eggs and the vanilla and mix, scraping the bowl down.

On the lowest setting add a third of the dry mixture, then half the milk and half the sour cream, another third of the dry, the rest of the milk and sour cream, then the last of the dry. The batter is very loose.

Scrape the bowl down, add the hot coffee and whisk to a uniform consistency.

Divide the batter equally between the pans and bake at 350F for 40 to 45 minutes, until the centres are set and the edges pull away from the pan.

Cool the layers completely in the pan.

For the buttercream, whip the room temperature unsalted butter on high five minutes until light and cloudy.

Add the cocoa powder, salt and vanilla and mix on low until combined.

Add the powdered sugar a cup at a time on low, then thin with the cream.

Knock the big air bubbles out with a spatula for a silky look.

Put a dollop of buttercream on the cake plate as glue, turn out the first layer, frost the top and smooth it to the edge, then add the second layer.

Cover the whole cake in frosting and finish with wavy swoops using an offset or rubber spatula.