Put bread crumbs in large bowl. Pour milk over bread crumbs. Stir until blended.
Add beef, egg, grated onion, salt, msg, nutmeg and pepper to bread crumb mixture. Mix lightly until thoroughly blended. Shape into small patties 2 1/2 inch diameter and 1/4 inch thick.
Heat 3 tbsp butter in large skillet with lid. Add patties to skillet, cook over medium heat until well browned. Turn and brown second side. Cover and set aside to keep warm.
Clean and slice onion thinly. Heat 2 tbsp butter in small skillet. Add onion and cook over medium head until lightly browned. Remove onion and set aside. Drain fat from skillet. Add 1 tbsp sugar. Stirring constantly with back of wooden spoon, head until sugar is melted. Add meat broth gradually, then 2 tbsp butter. Stir until blended.
Pour broth over meatballs. Cover meat with onion slices. Cover skillet and simmer 10 minutes. Serve over egg noodles.