Preheat oven to 350 degrees F (175 degrees C). Grease and flour two eight inch round pans.
In a large bowl, stir together the sugar, flour, cocoa, baking powder, baking soda and salt. Add the eggs, milk, oil and vanilla, mix for 2 minutes on medium speed of mixer. Stir in the boiling water last. Batter will be thin. Pour evenly into the prepared pans.
Bake 30 to 35 minutes in the preheated oven, until the cake tests done with a toothpick. Cool in the pans for 10 minutes, then remove to a wire rack to cool completely.