Preheat oven to 425°F; grease a 8-inch square baking pan and set aside. Combine dry ingredients in a mixing bowl and stir well. In a separate bowl, whisk together the milk, egg and melted butter. Pour the liquid ingredients into the flour mixture and stir just until all the dry ingredients are moistened. Spread batter in prepared pan and bake in preheated oven about 20 minutes or until a toothpick inserted in center comes out clean.