In a food processor blend the cherry preserves until almost smooth. Transfer the preserves to a large, heavy saucepan. Add the pomegranate juice and bring to a boil. Continue to boil until the mixture thickens slightly and is reduced to 480 millilitres, 20 to 25 minutes, stirring often and adjusting the heat as needed to prevent overflowing (the mixture will boil up to the top of the pan while cooking). Remove from the heat and stir in 4 teaspoons of the chile peppers, coriander and cumin. Taste and add more chile if more heat is desired. Cool completely (the glaze will thicken as it cools). Transfer 240 millilitres of the glaze to a small bowl and set aside for serving. Set aside the remaining 240 millilitres of glaze for basting. (The glaze can be made one day ahead. Cover and refrigerate. Let stand at room temperature 1 hour before using.)
In a small bowl combine the rub ingredients. Using a dull dinner knife, slide the tip under the membrane covering the back of each rack of ribs. Lift and loosen the membrane until it breaks and then grab a corner of it with a paper towel and pull it off. Brush each rack all over with the oil and season the racks with the rub, putting more of it on the meaty sides than on the bone sides. Allow the ribs to stand at room temperature for 30 minutes before grilling.
Related Grill Skills
Removing the Membrane from Baby Back Ribs
Prepare the grill for indirect cooking over medium–low heat (150°C to 180°C).
Brush the cooking grates clean. Grill the racks, bone-side down, over indirect medium–low heat, with the lid closed, until the meat is very tender and has shrunk back from most of the bones by 0.5 centimetre or more, 3 to 3½ hours. Lower the temperature of the grill if the ribs are browning too quickly.
During the last 20 to 25 minutes of grilling time, baste the racks generously with the reserved glaze every 5 to 10 minutes. Remove from the grill and let rest for 5 to 10 minutes. Cut the racks into individual ribs. Serve with the remaining glaze for dipping.