Soft, moist, and smooth chocolate layer cake with the richest chocolate flavor you’ll ever taste. Super easy and only one bowl needed! Pair with my favorite chocolate buttercream, go-to vanilla buttercream, or something fancier to fit your liking.
In a large bowl, stir together granulated sugar, flour, baking soda, baking powder, and salt. Sift in cocoa powder and stir combine.
Add the eggs, buttermilk, oil, and vanilla and stir well until batter is smooth.
Brew a cup of coffee and microwave until boiling.
Slowly add coffee to batter and stir until blended well. Be sure to scrape the bottom of the bowl to make sure everything gets mixed together. Batter will be very thin.
Pour batter into prepared pans and bake for 28 to 30 minutes or until toothpick inserted in center comes out clean. Cool on wire racks completely before assembling and frosting.
In a large bowl with a handheld mixer, or a stand mixer fitted with the paddle attachment, beat the butter on medium speed until creamy, about 2 minutes.
With the mixer on low, add in the powdered sugar, vanilla, and milk or cream. Increase mixer speed to medium and beat until completely smooth, about 3 minutes. If frosting is too stiff, add more milk. If it is too thin, add more powdered sugar. Add salt to taste.
In a medium size bowl with a handheld mixer or in the bowl of stand mixer fitted with the paddle attachment, beat butter on medium speed until smooth (about 3 minutes).
Decrease mixer speed to low. Add powdered sugar, cocoa, vanilla extract, and milk/cream. Increase mixer speed to to high and beat until completely combined (approximately 2-3 minutes).
TO ASSEMBLE CAKE
Place one layer, bottom side up, on a plate or cake stand. Using a spatula or knife, spread an even layer of frosting over the entire surface.
Place the second layer on top, bottom side down, and press down on the top lightly. Spread the rest of the frosting on the cake, beginning with the top and working your way down the sides. Decorate as desired. Cake stays fresh covered at room temperature for up to 4 days. Cake may be covered and refrigerated for up to 7 days.