Place ground beef in a medium bowl. Microwave at high (100%) 6 to 8 minutes, stirring to break up beef after half the cooking time. Add seasonings and tomato sauce. Microwave at high (100%) until mixture boils, 6 to 8 minutes. Stir. Microwave at medium (70%) 5 to 6 minutes. Meantime, cook noodles as directed on package and set aside. In a separate bowl mix together chopped onion, cream cheese and sour cream. In a 2 quart casserole layer noodles, meat sauce and sour cream mixture, repeating layers. Cover. Microwave at high (100%) for 8 minutes. Uncover. Sprinkle with grated cheese. Microwave at high (100%) until cheese melts, 2 to 3 minutes. Makes 6 to 8 servings.