How to Make It
Preheat the oven to 300°. In a spice grinder, pulse the caraway seeds to a coarse powder. Add the pimentón, cumin, garlic powder, salt and pepper and pulse to blend. Transfer 2 tablespoons of the spice mixture to a small saucepan and stir in the apricot preserves and mustard.
Using a kitchen towel, grasp and pull off the papery membrane from the underside of each rack of ribs. Place the ribs side by side in a large roasting pan and rub both sides with the remaining spice mixture. Cover tightly with foil and roast for 1 1/2 hours, or until the meat is almost tender.
Pour the pan juices into the saucepan with the apricot preserves. Cover the ribs again and roast for about 30 minutes longer, until very tender. Pour any remaining pan juices into the saucepan.
Preheat the broiler. Bring the pan juices and apricot preserves to a boil and simmer over moderate heat until slightly thickened, about 10 minutes.
Arrange the rib racks concave side up; brush them with half of the apricot glaze, allowing it to pool in the center of the rack. Broil the ribs 10 inches from the heat until browned, about 10 minutes. Turn the racks over, brush with the remaining apricot glaze and broil until caramelized, about 10 minutes. Transfer the rack to a cutting board and cut into ribs.