Preheat oven to 350 degrees Fahrenheit. Butter three 9-inch round cake pans. Dust with flour and tap out the excess.
Mix flour, sugar, cocoa, baking soda, baking powder, and salt in a stand mixer using a low speed until combined.
Add eggs, buttermilk, warm water, oil, and vanilla. Beat on medium speed until the batter is well combined and smooth. Take care not to over beat it.
Divide the batter amongst three pans.
Bake for 30-35 minutes or until a toothpick inserted into the center comes out clean.
Cool on a wire rack for 10-15 minutes then turn out the cakes onto the racks and allow to cool completely.
Layer and frost with your favorite frosting and enjoy!