---------------------------------MEAT LOAF--------------------------------1 1/2 lb Ground beef 3/4 c Quaker Oats, uncooked -(quick or old-fashioned) 1 Egg 2 ts Salt 1/4 ts Pepper 1 ts Worcestershire sauce 2/3 c Milk For filling, lightly brown mushrooms and onion in butter in medium-sized skillet. Remove from heat; stir in sour cream. For meat loaf, combine all ingredients thoroughly. Place half of meat mixture in shallow baking pan. Shape to form an oval base. Lengthwise down the center make a shallow "well" for the filling. Spoon filling into "well". Shape remaining meat mixture over filling, making sure all filling is covered. Seal bottom and top meat mixtures together. Bake in preheated moderate oven (350 F.) about 1 hour. Let stand 5 minutes before slicing.