Preheat the oven to 350 degrees F. Coat the bottom of a 13 x 9 x 2-inch baking pan with nonstick vegetable-oil cooking spray.
Gently combine ground beef, bread crumbs, milk, egg, Worcestershire, pepper and onion salt in a large bowl. Place the meat mixture in a mound in the prepared baking pan. Using clean hands, gently form the meat mixture into a loaf shape in the pan.
Combine ketchup, mustard and brown sugar in small bowl. Spread over the shaped meat loaf.
Bake in 350 degree F oven for 1 hour or until internal temperature registers 160 degrees F. Remove from oven, slice and serve hot. Makes 6 servings.