1. Preheat oven to 350°F.
2. Trim fat from pork chops. Season chops with sage, salt, and pepper.
3. Place pork chops in a casserole. Top with onion and apples. Sprinkle with brown sugar.
4. Bake covered for 2 1/2 hours. Remove cover, baste with pan juices. Bake 30 minutes till tender. Remove chops and vegetables from pan and keep hot.
5. Stir flour into drippings until smooth. Stir in cream, mustard, and cayenne pepper. Boil 1 minute, stirring. Place chops in serving dish, top with vegetables and sauce.