01 -
Turn on your oven to 350°F (177°C). Grease two 8-inch pans lightly and add parchment to the bottoms.
02 -
Grab a big mixing bowl and whisk together cocoa powder, flour, baking soda, baking powder, salt, and espresso powder until they blend nicely.
03 -
In a separate bowl, mix the melted butter, oil, sugars (both kinds), eggs, sour cream, milk, and vanilla. Stir until smooth.
04 -
Take turns adding a portion of the dry mix and the coffee to the wet bowl. Start with dry, then coffee, dry again—repeat until done. Whisk gently between each step.
05 -
Divide the batter evenly into the pans, about 675g each. Bake for 33-38 minutes. Let the cakes rest in pans 15 minutes, then move to a rack to fully cool (30-60 minutes).
06 -
While waiting, mix sugar, water, sifted cocoa powder, brewed coffee, and vanilla in a small pot. Heat until bubbling over medium-high, about 4-5 minutes, so it thickens slightly. Cool down completely off the heat.
07 -
If you prefer a flat surface, carefully trim uneven tops off the cakes. This also allows syrup to soak better.
08 -
Make sure the syrup is at least warm, not hot. Brush it onto your cake layers, about 2-3 tablespoons (30-45 ml) for each. Chill cakes for at least 1-2 hours before moving on.
09 -
Using a mixer, whip butter until smooth (about 1-2 minutes at low). Add vanilla, salt, heavy cream, and brewed espresso. Gradually stir in sifted powdered sugar, about 60g at a time. Once all added, beat briefly on medium-high for a creamy texture.
10 -
Smear some frosting on a serving plate or cake stand. Lay down one cake layer. Cover completely with frosting, spreading some beyond the edges. Add the second layer on top and frost again, smoothing it down to form a thin, protective crumb layer.
11 -
Let the almost-finished cake sit in the fridge about 20-30 minutes. This sets the base, so the final frosting layer goes on easily.