1 pound boneless beef sirloin steak or beef top round steak
2 tablespoons vegetable oil
1 medium onion, chopped
1 (10.75 ounce) can Campbell's?(r) Condensed Cream of Mushroom Soup or Campbell's?(r) Condensed 98% Fat Free Cream of Mushroom Soup
1/2 teaspoon paprika
1/2 cup sour cream or yogurt
4 cups hot cooked medium egg noodles
Chopped fresh parsley