French the lamb racks
Mix the paste ingredients in a small bowl. Spread the paste over the lamb racks and allow them to stand at room temperature for 20 to 30 minutes before barbecuing.
Combine the orange juice, pomegranate juice, honey and balsamic vinegar in a small saucepan over a high heat and bring to the boil. Once boiling, reduce the heat to medium and simmer for 15 to 20 minutes until the liquid has reduced to about 5 tablespoons. Season the light syrup with the salt and allow to cool. (You can refrigerate the syrup for up to 3 days.)
Prepare the barbecue for direct cooking over a medium heat. Brush the cooking grills clean. Barbecue the lamb, bone sides down first, over direct medium heat, with the lid closed as much as possible but turning once or twice and moving the racks over indirect heat if flare-ups occur, until cooked to your desired doneness, 15 to 20 minutes for medium rare. Remove from the barbecue when the internal temperature reaches 52°C (125°F). Allow the lamb to rest for 5 minutes before carving into chops (the internal temperature will rise during resting).
If necessary, warm the syrup over a low heat until it reaches your desired consistency. Serve the lamb warm with the syrup drizzled on top.