In a small saucepan combine the apple cider, shallot, and jalapeño. Bring to a boil and cook over medium-high heat until about 1 cup of the liquid remains, 15 to 20 minutes. Add the remaining mop ingredients, bring to a boil, and remove from heat. The mop can be made ahead and refrigerated until ready to use.
Using a dull knife slide the tip under the membrane covering the back of each rack of ribs. Lift and loosen the membrane until it breaks, then grab a corner with a paper towel and pull it off. Season the racks evenly with salt and pepper. Allow the racks to stand at room temperature for 15 to 30 minutes before grilling.
Prepare the grill for indirect cooking over medium heat (350° to 450°F).
Brush the cooking grates clean. Grill the racks, bone side down, over indirect medium heat, with the lid closed as much as possible, until the meat is very tender and has pulled back from the ends of the bones, 1½ to 2 hours. Baste the ribs frequently with the mop throughout grilling time, but stop basting during the last 10 minutes. Remove from the grill and allow to rest for 5 to 10 minutes before slicing into individual ribs. Serve warm.