Combine ingredients in a large plastic bag. Marinate lamb for one hour up to one day. After marinating, let sit at room temp for at least 20 minutes before you grill. Meanwhile, heat up the grill.
Grill for 6 minutes with the meat side down. Then, flip over and grill 3 minutes with the fat side down.
Next, flip once more to meat side down, then turn heat to low. Let lamb rack sit for 10 minutes on low heat. Remove from grill and set rest for at least 10 minutes. Note: this is for medium rare-medium doneness. If in doubt, check temperature using an instant thermometer and cook longer if needed.
Slice lamb and serve!