Place ribs in nonreactive, plastic, bowl with a lid. In a separate bowl, combine marinade ingredients; sugar, sherry, hoisin sauce, garlic, salt (if desired) and ketchup. Mix well and spoon over ribs. Place cover on bowl and shake to coat ribs thoroughly with marinade. Place in refrigerator and marinate for 4 hours or longer. Shake once or twice while marinating to coat again.

To avoid mess, cover cookie sheet with aluminum foil. Take ribs from refrigerator and shake to coat again. Place ribs on their sides on cookie sheet. Don't crowd, or they won't be crispy. Bake at 350 degrees for 30 minutes. Turn over with tongs and bake additional 20- 30 minutes. Check carefully last 10 minutes of baking to prevent burning.