In a mixing bowl, combine minced garlic, lemon juice, olive oil, rosemary, salt, pepper, and lemon zest if using. Whisk until well blended.
Place the lamb chops in a large resealable plastic bag or shallow dish. Pour the marinade over the chops, ensuring they are well coated. Seal the bag or cover the dish, and refrigerate for at least 1 hour, or up to 8 hours for more flavor.
Preheat your grill or a grill pan over medium-high heat. Remove the lamb chops from the marinade and let any excess drip off.
Grill the lamb chops for about 4-5 minutes on each side for medium-rare, or until they reach your desired doneness. Use a meat thermometer to check; the internal temperature should be 145°F for medium-rare.
Remove the lamb chops from the grill and let them rest for 5 minutes before serving. This helps retain the juices.
Serve with your favorite sides, such as roasted vegetables or a fresh salad.