1. Prepare a grill for indirect cooking over low heat (about 300 degrees F). (See "indirect grilling," below).
2. For rub, in small bowl mix together the first 7 ingredients.
3. Using a dull dinner knife, slide the tip under the membrane (silver skin) covering the back of each rack of ribs. Lift and loosen membrane until it breaks loose from the meat. Using paper towels to grip, pull membrane off. Season ribs all over with the rub. Arrange in a rib rack, all facing the same direction. Let the ribs stand at room temperature for 30 minutes before grilling.
4. Just before grilling ribs, drain 2 handfuls of wood chips and place them on coals or in smoker box of a gas grill. When the wood begins to smoke, place ribs over indirect low heat and cook for 1 hour.
5. After 1 hour, drain the remaining wood chips and place on coals or in smoker box of a gas grill. Continue to cook ribs over indirect low heat for a second hour. Meanwhile, prepare Fresh Ginger Glaze.
Fresh Ginger Glaze:In small saucepan over medium heat, combine the glaze ingredients. Bring to simmer, stirring occasionally, and cook over low heat for about 3 minutes. Remove from the heat.
7. Tear off 3 sheets of aluminum foil, each about 2 1/2 times the length of a slab of ribs.
8. After 2 hours of cooking, remove ribs from rack and lay each slab on a sheet of foil. Be sure to close the grill lid so that the temperature remains close to 300 degrees F. Brush each slab lightly on both sides with some of the glaze (you will not need all of it). Wrap each slab of ribs tightly in foil.
9. Return slabs to the grill, either in rack or stacked on top of each other. Cook over indirect low heat until glaze cooks into the meat and ribs are done, 30 to 60 minutes. The ribs are done when the meat has shrunk back from the bones by 1/4 inch or more. When you lift a rack by picking up one end with tongs, the rack should bend in the middle and the meat should tear easily. If the meat does not tear easily, continue to cook the ribs.
10. Remove slabs from foil. Brush them with some of the remaining glaze. Cut into portions. Serve with grilled bok choy and lemon halves.
Note: For a charcoal grill, you may need to cut rib slabs in half to fit for indirect cooking.
Indirect grilling: This method positions the fire to one side or both ends of grill. Food sits over the unlit part, and the grill is covered so the food cooks from all sides. This is best for thicker cuts that need longer cooking like roasts and ribs.