In a saucepan, sauté onion and mushrooms in 2 tablespoons of butter until tender.

Stir in the tomato sauce, Parmesan cheese, 1/4 cup parsley and spaghetti sauce mix. Bring to a boil. Reduce heat, cover and simmer for 15 minutes, stir occasionally.

In a shallow dish, combine flour, onion salt and garlic salt; coat duck pieces.

In a large skillet, brown duck on both sides in remaining butter. Place in an ungreased 13 in x 9 in x 2 in baking dish. Top with tomato mixture; sprinkle with cheeses.

Bake, uncovered, at 375°F for 28-32 minutes or until meat thermometer reads 180°F. Sprinkle with remaining parsley. Serve with pasta.