In a small bowl, combine baking mix and sugar. In another bowl, whisk egg and milk; stir into dry ingredients just until moistened. Spread into an 8x4-in. loaf pan coated with cooking spray. In another bowl, combine the brown sugar, flour and cinnamon; cut in butter until crumbly. Sprinkle over batter.
Bake at 400° for 15-20 minutes or until a toothpick inserted in the center comes out clean. Cool on a wire rack.