For Cake

1. Preheat oven to 350 degrees
2. Spray three 8-inch cake pans with nonstick cooking spray
3. Line bottoms of the pans with parchment paper cut to fit
4. In a large bowl, whisk to combine flour, sugar, cocoa powder, baking powder and baking soda
5. Set aside
6. In a separate bowl, whisk together buttermilk, vegetable oil, vanilla, cooled espresso and eggs until combined
7. Slowly add the wet ingredients in to the dry ingredients and stir until just barely combined, less than 30 seconds
8. Do not over mix
9. Divide batter evenly into the three prepared cake pans
10. Bake at 350 degrees for 18-20 minutes, checking at 15 minutes to be sure cakes are not over baking. Cake will be done when edges of cake pull away from sides of pan and a toothpick inserted near the center of cake comes out with few crumbs
11. Remove from oven and cool on a wire rack for 20 minutes
12. Remove cakes from pans by inverting cake onto a plate or platter, tapping bottom of cake pan if needed
13. Peel away parchment paper from bottom of cakes
14. Allow to cool completely before frosting

For Frosting

1. In the bowl of a stand mixer, cream butter on high for 3-4 minutes, scraping down sides of bowl as needed
2. Add vanilla, cocoa powder, espresso and pinch of salt and mix on low for 30 seconds
3. Increase speed to high and mix for 1 additional minute
4. Carefully add sifted confectioner’s sugar to the mixer and mix on low until combined
5. Increase speed to high and mix for 4-5 minutes, scraping sides of bowl as needed
6. Stop mixer and add heavy whipping cream
7. Return mixer to high speed and mix and additional 2 minutes until frosting is light and fluffy
8. Add more heavy whipping cream if frosting is too stiff

To Assemble Cake

1. Once cake has cooled completely, level tops of cakes with a large knife or cake cutter so that tops of cakes are all flat
2. Place a small dollop of frosting on a plate or cake platter and place first layer of cake top-side down on the platter
3. Place 1/3 cup of the frosting on top of the layer and spread evenly using an offset spatula
4. Place the next cake layer bottom-side down and repeat with 1/3 cup frosting
5. Place the final layer of cake bottom side up and check to be sure cake is level, adjusting as needed
6. Frost top of cake with another 1/3 cup frosting and begin to work some of the frosting down the sides of the cake to make the first crumb coat of frosting
7. The cake will not be completely frosted at this point
8. Place the cake in refrigerator for 30 minutes
9. Remove cake from refrigerator and continue to frost the cake completely using remaining buttercream
10. Spread the frosting smooth using a bench scraper and offset spatula or use a butter knife or back of a spoon to create swooshes of frosting across the cake top and sides