Combine the dry ingredients. Preheat the oven to 350 degrees and line 3 cake pans with parchment paper. In a large bowl combine the flour, cocoa powder, sugar, baking powder, baking soda and salt. Set aside.
Mix the wet ingredients. To the bowl of a stand up mixer add the oil, eggs and vanilla and beat on medium speed until combined. Add the buttermilk and mix until combined.
Add the dry ingredients into the wet. Add the flour mixture into the mixing bowl and add the hot coffee. The hot coffee will help break down the cocoa and deepen the chocolate flavor. You can use decaf! Mix until just combined, the mix will be thin.
Bake the cake. Pour the cake batter evenly into the 3 pans. Bake for 23-25 minutes. The cake may sink a little in the middle but this is normal for a cake made with cocoa. Don't worry if this happens it will even out when layered!