Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9x13 inch pan.
In a large bowl, stir together the flour, sugar, cocoa, baking powder, and baking soda. Add the oil, milk, eggs, and vanilla, mix until smooth. Stir in the hot coffee last. Spread evenly into the prepared pan.
Bake in the preheated oven for 25 to 35 minutes, or until a toothpick inserted into the cake comes out clean.