Preheat the oven to 350°F. Spray 2, 8-inch x 3-inch round cake pans with nonstick cooking spray. (8-inch cake pans with shorter sides may cause an overflow in your oven.) Set aside.
To the bowl of a stand mixer, add the flour, sugar, cocoa, baking soda, baking powder, and salt. Mix to combine.
In a separate bowl, combine the buttermilk, oil, eggs, and vanilla.
With the mixer on low speed, slowly add the wet ingredients to the dry. With the mixer still on low, add the coffee and stir just to combine, scraping the bottom of the bowl with a rubber spatula.
Pour the batter into the prepared pans and bake for 30-40 minutes, or until a cake tester or toothpick comes out mostly clean with no wet batter.
Let the cakes cool in the pans for 30 minutes. Then, turn them out onto a cooling rack to let them cool completely.