Preheat oven to 350 degrees.
Grease and flour two 9 inch pans, line bottom with parchment paper circles and set aside. I USED THREE 6 INCH PANS. THIS WILL MAKE TWO SMALL 3 LAYER CAKES.
In a bowl or stand mixer, stir together flour, cocoa, sugar, baking soda, and salt.
Add eggs, buttermilk, melted butter, and vanilla beat until smooth, about 2 to three minutes.
Remove bowl from mixer and stir in hot coffee with rubber spatula; the batter will be very runny.
Pour into pans and bake on middle rack for 35 minutes or until toothpick comes out clean with a few crumbs attached.
Allow to cool on wire rack for 15 minutes,.
Run a butter knife around the pans.
Invert pans onto rack.
Cool completely before frosting.