Preheat oven to 350 F.
In a mixing bowl, combine flour, sugar, and salt.
In a saucepan, melt butter. Add cocoa. Stir together.
Add hot coffee, allow mixture to boil for 30 seconds, then turn off heat. Pour over flour mixture and stir lightly to cool.
In a measuring cup, combine the buttermilk, beaten eggs, baking soda, and vanilla. Stir buttermilk mixture into butter/chocolate mixture. Pour into cake pans and bake at 350-degrees for 30-40 minutes. They are done when a toothpick comes out clean or the middle firms up and springs back when lightly pressed.