Trim fat from lamb chops; set chops aside. In a small bowl combine garlic, fennel seeds, cumin, coriander, salt, and pepper. Sprinkle evenly over all sides of lamb chops; rub in with your fingers. Place lamb chops on a plate; cover with plastic wrap. Chill for 30 minutes to 24 hours.
For a charcoal grill, place lamb chops on the rack of an uncovered grill directly over medium coals. Grill until desired doneness, turning once halfway through grilling. Allow 12 to 14 minutes for medium-rare doneness (145°F) or 15 to 17 minutes for medium doneness (160°F). (For a gas grill, preheat grill. Reduce heat to medium. Place chops on grill rack over heat. Cover and grill as above.)