Lightly combine first 4 ingredients. Form into 16 meatballs. In large skillet partially brown meatballs in shortening. Drain off excess fat. Drain mushrooms, reserving liquid. Stir mushrooms and onion nto skillet; saute until onion is tender. Stir in flour, then reserved mushroom liquid, water, 57 sauce, and parsley. Cover; simmer 25 minutes, stirring occasionally. Slowly stir in sour cream; heat. Do not boil. Serve immediately over noodles.