Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9x13 inch pan. In a small bowl, dissolve the cocoa in the hot coffee; set aside. Sift together the flour, baking soda, baking powder and salt. Set aside.
In a large bowl, combine the sugar, oil, eggs and vanilla. Beat in the flour mixture alternately with the cocoa mixture. Pour batter into prepared pan.
Bake in the preheated oven for 40 to 50 minutes, or until a toothpick inserted into the center of the cake comes out clean. Allow to cool.