Stir sugar, cocoa powder, butter, and 7 tablespoons milk together in a saucepan; bring to a boil. Cook, stirring constantly, at a boil for 2 minutes. Remove immediately and put saucepan in a sink with 1 inch cold water in it to cool the frosting. Add remaining milk and vanilla extract to the frosting; stir until thick.
All done! Now take a photo, rate it, and share your accomplishments!