Mix together the egg and 1/2 cup milk, pour over the torn up bread in bowl. Then add the hamburger, onions, dried mustard, celery salt, nutmeg, salt and pepper; mix till well combined. Shape into golf ball size meatballs. Dust meatballs lightly in flour. Brown meatballs in about 2 tablespoons Crisco till nicely browned (about10-15 minutes); set aside. In same pan add the 3/4 cup milk with the cream of mushroom soup, cook till smooth and bubbling, stirring constantly. Then add in frozen veggies such as peas and carrots, or whatever you like. Then either add meatballs back into sauce or serve separately for people who don't want sauce. Serve with either boiled potatoes or rice. (may double the sauce recipe if desired).