This mocha layer cake with coffee frosting is tastes amazing! The chocolate cake has plenty of strong coffee baked into it, a coffee simple syrup drizzled into the baked cake, loads of coffee frosting and a delicious semi-sweet ganache finish!
Preheat oven to 350 degrees F. Spray 3 8-inch round cake pans with nonstick cooking spray. Place a circle of parchment paper in the bottom of each pan.
In a medium microwave-safe bowl, add in the 3/4 cup butter and the 1 cup strong coffee. Microwave for 2 minutes or until the butter is completely melted.
Add in the 2 tablespoons vegetable oil and 3/4 cup unsweetened cocoa powder and whisk until smooth.
Add in 1 cup full-fat sour cream and 2 teaspoons vanilla extract. Continue to whisk until the sour cream in incorporated.
In a separate large bowl, add in 2 cups cake flour, 1 1/2 cups granulated sugar, 1 1/2 teaspoons baking soda, 1/2 teaspoons baking powder, 1/2 teaspoons salt, and 1 teaspoons espresso powder. Whisk until combined.
Pour the cocoa mixture in with the dry ingredients.
Add in the lightly beaten 2 large eggs. Whisk until most of the lumps are gone and the dry ingredients are incorporated.
Divide the batter into the 3 prepared cake pans. You can wrap the pans with Wilton's even baking strips to help make them level.
Bake for 24 - 26 minutes or until they're done. Place a toothpick in the center of the cake and if it comes out clean or with moist crumbs it's done. If there's batter on the toothpick, let the cakes bake a few minutes longer and test them again.
Let the cake cool in the pan for about 15 minutes and then turn out onto a cooling rack to finish cooling.
Frosting
In a large mixing bowl, add in the 2 cup butter. Mix with the hand mixer until the butter is creamy.
In a small bowl, add the 6 tablespoons instant coffee granules and 6 teaspoons water. Mix until all the granules are dissolved.
Add the coffee mixture and 6 cups powdered sugar in with the butter. Mix until it comes together.
Add in the 5 tablespoons whole milk and continue to mix for about 2 minutes. It will make the buttercream light and fluffy.
Ganache
In a microwave-safe bowl, add in the 1 cup semi-sweet chocolate chips, 1/2 cup heavy cream, and pinch of salt. Stir to combine.
Microwave for 30 seconds. Stir. Repeat microwaving for 30 seconds and stirring until everything comes together and is smooth.
Place in the fridge for about an 30 minutes to an hour to cool down and thicken to a spreadable consistency.
Assemble
Trim the tops of the cakes if they have a dome so they are flat and level.
Drizzle 2 - 3 tablespoons of the coffee syrup on the first cake.
Add a generous layer of coffee frosting to the cake. Make sure to level the frosting out so there's a flat surface for the next layer.
Add the second cake. Repeat the drizzle of coffee syrup and coffee frosting.
Add the top layer of cake.
Drizzle the coffee syrup on top of the cake.
Add a thin layer of frosting all over the cake to fill in any grooves and catch all of the crumbs. This is the crumb coat. Let it sit and form a crust. This will take maybe 10 - 15 minutes.
Add a couple large scoops of frosting to the top of the cake. Using an offset spatula, flatten it and let the excess frosting start working its way down the sides of the cake.
Once the top of the cake is flat, work the frosting down the sides of the cake. Grab more frosting as needed. You can use a bench scraper or a large offset spatula to smooth the sides of the cake.
For a drizzle of ganache, add it into a sandwich bag or disposable piping bag. Cut a small hole and drizzle it down the sides of the cake. For a shell of ganache on the sides of the cake, place the warm ganache in the fridge for about 30 minutes or until it becomes a spreadable consistency. Spread it on the sides of the cake.
Place the remaining coffee frosting into a piping bag fitted with a 1M tip. Pipe swirls on the top of the cake.