Preheat oven to 350 degrees F (175 degrees C). Grease and flour one 9x13 inch pan.
In large bowl combine flour, sugar, cocoa, baking soda, baking powder and salt. Make a well in the center.
Add eggs, coffee, buttermilk, oil and vanilla. Beat for 2 minutes on medium speed. Batter will be thin. Pour into prepared pans.
Bake for 30 to 40 minutes, or until toothpick inserted into center of cake comes out clean.
Cool then frost with Fudge Frosting