This Devil's Food Cake is a traditional chocolate cake that is light and fluffy and has a moist crumb. It's made with cocoa powder, buttermilk, and NO coffee!
Preheat oven to 350°F. Line two 9" cake pans with parchment paper, grease the sides, and set aside.
Whisk the flour, cocoa powder, baking soda, baking powder, salt together in a large bowl; set aside. Using a handheld or stand mixer fitted with a whisk attachment beat the eggs on medium just until combined. Add the sugars and beat on high until light and fluffy and doubled in size.
Fit mixer with the paddle attachment and add butter a little at a time (about 1 tablespoon at a time), and mix for 10 seconds after each addition scraping the bowl as needed. The batter may appear curdled and that is OK. Add the vanilla.
Add flour mixture in 3 additions, alternating with 2 additions of buttermilk mixing just until incorporated after each addition. Scrape down the bowl as needed. After the additions mix on medium speed just until thoroughly combined.
Divide batter evenly between prepared pans. Bake for 30 minutes or until a toothpick inserted in the center comes out with a few crumbs. Let the cakes cool in the pans for 10 minutes before removing from the pans to cool completely on wire racks.
In a stand mixer fitted with a paddle attachment beat the butter until pale in color. Add remaining ingredients and mix on low until combined then beat on high until light and fluffy (about 3 minutes). If the frosting seems too thin add a little confectioners' sugar. If it is too thick add a little more cream.
Place 1 cake layer on a serving platter or cake stand. Spread an even layer over the top. Place second cake layer on top and frost the top and sides with remaining frosting. If desired make pretty swirls in the the frosting.
Store cake in the refrigerator for 3-5 days.