Preheat the oven to 350°F. Prepare two 9-inch circle pans with a layer of parchment, then spray well with baking spray. For a parchment tutorial, see the link in the post above.
In the bowl of a stand mixer or in a large bowl with hand beaters, combine all the dry ingredients on low until evenly mixed. Use a rubber spatula to help as needed.
2 cups all-purpose flour, 2 cups granulated sugar, 1 cup cocoa powder, 2 teaspoon baking soda, 1 teaspoon baking powder, 1 teaspoon kosher salt
Add all the wet ingredients. Mix on low until combined, scraping the sides and bottom well.
3 eggs, 1 cup buttermilk, 1 cup very hot coffee, ⅓ cup vegetable oil, 1 teaspoon vanilla
Divide batter evenly into prepared pans. Tap the pans on the counter a few times to release excess air bubbles.
Bake on the middle rack for about 30 minutes, or until a toothpick inserted in the middle of the cake comes out clean or with only a few small, moist crumbs.
Allow to cool in the pan for 15 minutes, then flip onto a wire rack to cool completely.