.Preheat oven to 350 degrees. In a small skillet sautee onions until translucent but not brown. In a large bowl combine beef, egg, onion, milk, worcestershire and bread crumbs. Season with salt and pepper and mix well. Place beef mixture in lightly greased loaf pan. In a seperate bowl combine brown sugar, mustard and ketchup, mix well and pour over meatloaf. Bake for1 hour at 350 degrees.