2cups(16 ounces) unsalted butter, at room temperature
2cups(16 ounces) cream cheese, at room temperature
1tablespoonpure vanilla extract
8cups(32 ounces) confectioner's sugar, sifted
For the Chocolate Cake
Position a rack in the center of the oven and preheat the oven to 350°F. Generously spray three 8-inch cake pans with cooking spray and line the bottom of each with a parchment paper circle. Spray the parchment, too.
In a medium bowl, whisk together the flour, sugar, cocoa powder, baking soda, baking powder, and salt.
In a large bowl, whisk together the buttermilk, oil, eggs, and vanilla. Gradually whisk in the dry ingredients until just combined. Slowly pour in the coffee. The batter will be fairly runny; use a rubber spatula to scrape down the bottom and sides of the bowl. Use the rubber spatula to finish mixing until smooth and well combined, 2 to 3 minutes more.
Divide the batter evenly between the pans; if using a digital scale to measure out layers, note that this recipe makes around 72 ounces of batter—pour 24 ounces of batter into each cake pan. Bake for 35 to 40 minutes. When done, the top of the cake should bounce back when gently pressed and a skewer inserted into the center of the cake should come out with a few crumbs attached. Cool completely in the pans on a wire rack before frosting.
For the Vanilla Cream Cheese Frosting
In the bowl of a stand mixer fitted with the paddle attachment, beat the unsalted butter on medium-low until soft and creamy, 2 to 3 minutes. Scrape down the bottom and sides of the bowl with a rubber spatula. With the mixer on low, add the cream cheese, half cup at a time, scraping down the bottom and sides of the bowl as necessary. Once the cream cheese is combined, add the vanilla and salt, then beat on medium-high until the frosting is creamy and smooth, 1 minute. With the mixer on low, gradually add the confectioners' sugar and beat until combined. Scrape down the bottom and sides of the bowl once more, then beat on medium-high until the frosting is creamy and smooth, 2 to 3 minutes.