heat oven to 350 F and grease and line two 9 inch round pans
whisk flour sugar cocoa baking powder baking soda and salt
add eggs buttermilk oil and vanilla then mix until smooth
slowly mix in hot coffee until batter is thin and uniform
divide batter evenly and bake until a toothpick comes out with a few moist crumbs
cool in pans 10 minutes then turn out and cool completely.
Fudge Chocolate Frosting
beat butter until creamy
sift in powdered sugar and cocoa and beat on low then medium
add cream vanilla and salt and beat until fluffy and spreadable adding a splash more cream if needed.
Assemble
level cake layers if desired
frost one layer add second layer and frost top and sides
chill 20 minutes for cleaner slices then serve.
Notes
1. Use hot coffee for deeper chocolate flavor 2. Substitute buttermilk with 1 cup milk plus 1 tbsp lemon juice rested 5 minutes 3. For cupcakes bake 18 to 22 minutes 4. Cool cake fully before frosting to prevent melting