Preheat oven to 350° F. Spray two 9" round baking pans or one Bundt pan with nonstick spray, or line muffin cups with paper liners.
In a large bowl, whisk together the flour, sugar, cocoa, baking powder, baking soda and salt, breaking up any lumps of brown sugar and cocoa.
Add the milk, oil, eggs and vanilla and beat with an electric mixer on medium speed for about 2 minutes. Add the coffee and beat on low speed just until blended. The batter will be thin.
Divide the batter among the prepared pans and bake them for 30-35 minutes for layer cakes, 20-25 minutes for cupcakes or 50-55 minutes for a Bundt cake, until the top of the cakes are springy to the touch. Let them cool for about 10 minutes before running a knife around the edge of the pans and inverting them onto a wire rack. Cool completely before you frost them.