Melt butter in electric skillet. Add pork chops and brown slowly on both sides . Remove from skillet; add onion and saute until tender. Add tomato sauce, sp aghetti sauce mix and water. Mix well. Reduce heat to low; return pork chop s to skillet, cover and simmer 45 to 55 minutes or until tender. If sauce is t oo thick, add more water. Stir parmesan cheese into cooked sauce. Meanwhile, prepare spaghetti according to package directions; drain and arrange spaghetti and chops on serving platter. Spoon sauce over all. Sprinkle mozzarella chees e over pork chops. Serves 6.