Preparation

Prepare the wood chips and season the ribs

• Soak the wood chips in water for about 1 hour.

  Slide the blade of a dinner knife under the thin, translucent silverskin that covers the bone side of each rack (note that some racks are sold with the silverskin already removed). Lift and loosen the membrane until you can grab it with a paper towel; pull it off and discard.

  In a small bowl mix the spice rub ingredients. Sprinkle the rub all over the ribs, seasoning the meaty sides a little more than the bone sides and working the rub into the meat. Stand the ribs upright in a rib rack so that the meaty sides face the same direction. Leave as much room as possible between the racks; they shouldn’t touch. Let the racks sit at room temperature for 30 to 60 minutes while you prepare the grill.

Prepare the fire

• Open the vents on the bottom and top of the grill. Using a chimney starter or other method, light about 50 charcoal briquettes and let them burn until they are completely ashed over. Push the briquettes to one side and then spread them evenly to cover about one-third of the charcoal grate. Carefully set a large disposable drip pan on the opposite side of the charcoal grate and fill it about three-quarters full with warm water. Put the cooking grate in place, positioning a hinged section over the coals. Leave the lid off and let the briquettes burn until they are three-quarters of their original size and then close the lid. Let the fire burn down until a thermometer in the grill’s lid registers 300° to 325°F.

  Drain about half the wood chips and scatter them over the burning coals. (If your grill doesn’t have a hinged section, carefully lift the cooking grate off the grill, scatter the chips, and then replace the cooking grate.)

Start the ribs, mop, and sauce

• Set the rib rack on the cooking grate over the drip pan, with the bone sides of the ribs facing the coals. (The bones will protect the meat from cooking too quickly.) Let the ribs smoke for 45 minutes. Check every 10 minutes or so, and if the temperature rises above 325ºF, close the top vents halfway; otherwise, leave the vents completely open. If the temperature drops below 250ºF, add 5 to 10 unlit briquettes to the fire. After the ribs have cooked for 45 minutes, drain the remaining wood chips and gently spread them over the coals (don’t stir up any ashes). Close the lid. Let the ribs smoke 15 minutes more for baby backs, 1 hour 15 minutes more for spareribs.
• Meanwhile, make the mop and sauce: In a small measuring cup, mix the beer and 1/4 cup of the hoisin (this is the mop). In a small saucepan, mix the remaining 1/2 cup hoisin with the chili sauce, rice vinegar, and sesame oil. Bring to a simmer over medium heat and remove from the heat.

Baste the ribs and continue cooking

• Remove the ribs from the grill and from the rib rack and lay them on a large rimmed baking sheet. At this point, to maintain the heat, add about 10 unlit briquettes to the bed of burning coals and leave the lid off while you mop the ribs (the added oxygen will help light the new briquettes). Lightly brush the ribs on both sides with about half of the mop. Carefully put the ribs back in the rib rack, again all facing the same direction but this time turned upside down so that the parts that haven’t browned as much will get more exposure to the heat and smoke. Return the rib rack to the grill over the drip pan, again turning the bone sides toward the coals. Close the lid.

  让排骨煮到肉收缩1/4 1 /2 inch from the ends of at least several bones, 2 to 3 hours more, and then check them for doneness (see below). During this time, the fire should slowly lose heat, but if it falls below 250°F, add 5 to 10 unlit briquettes to maintain a temperature between 275º and 300°F. Also during this time, baste the ribs occasionally with the remaining mop (don’t bother removing them first from the rib rack). You may not use all the mop.

Finish the ribs

• When the rib meat has shrunk 1/4 to 1/2 inch from the ends of several bones, lift each rib rack one at a time from the metal rack, holding the meat at one end with tongs. Turn the ribs bone side up and let them hang so that the weight of the other end bends the rack in an arc. If the meat separates and tears easily near the middle of the arc (see photo), that rack is fully cooked. Some racks take longer than others, as long as 4 hours total cooking time for baby backs and 5 hours for spareribs.
• As each rack of ribs is fully cooked, lay it on a large sheet of heavy-duty aluminum foil. Lightly brush the ribs on both sides with the sauce—you may not need it all. Then wrap each rack individually in the foil. Let them sit at room temperature for 15 to 30 minutes for baby backs and 30 to 45 minutes for spareribs. Unwrap the racks, cut them into individual ribs, and serve warm.