Beat together the cheese, yogurt, green onion and parsley. Set aside. Saute onion in half the margarine until limp. Add mushrooms and remaining margarine and saute just until hot through. Set aside. Shape meat into 4 patties and place on a broiling rack. Season with salt and pepper and broil, turning to brown on both sides and cooking until medium rare. Spoon mushrooms over each patty and top with a dollop of cheese dressing. Return to the broiler just until cheese browns lightly. Makes 4 servings, at 310 calories per serving.
Source: Come Into the Kitchen