• Preheat oven to 350° F. Prepare four to five 7" x 2" round cake pans - I use cake release to prevent sticking.
• Melt butter in a large saucepan over medium-low heat; add cocoa, stirring until smooth. Whisk in the espresso water and remove from heat.
• Add the sugar, sour cream, vanilla, and eggs to the warmed cocoa mixture and whisk until smooth.
• In a medium bowl, combine the flour, baking soda, and salt. Add to the first mixture, whisking until well blended.
• Pour batter into the prepared pans. Bake for 30-35 minutes, or until it feels firm to the touch or an inserted toothpick comes out clean. Cool in pan on a rack for about 15 minutes.
• Remove from pan by placing the rack over the cake and invert, tapping pan lightly, if required to loosen.

To make the frosting:

• Mix vanilla and espresso powder together until dissolved. Using the whisk attachment of your mixer, whisk for 5 minutes, occasionally scraping down sides. On low speed, add powdered sugar a little at a time. I cover the mixer with a damp tea towel to contain the powdered sugar. When all powdered sugar is incorporated, turn up speed and beat until fluffy for about 2 minutes. Add vanilla-espresso mixture and whip until incorporated.

Assembly:

• Level the cakes using a large, serrated knife or other levelling tool (I use the Agbay Jr.). Fill each layer with generous amounts of frosting, wrap win plastic wrap and refrigerate for an hour. I find this helps the cake to settle and level itself and makes crumb-coating easier. Remove from fridge, add a thing layer of frosting refrigerate for 30 minutes and repeat. Refrigerate until firm enough to accommodate the stencil. Use a medium-size brush to add the cacao pattern.