Start by mixing all marinade ingredients in a small bowl. Let it sit for a good hour in room temperature so the flavors blend well. The reason for using just a small clove of garlic (or half a large one) is so the garlic won’t overpower the other flavors.
Trim the meat in the meantime (if needed).
Now brush liberal amounts all over the meat. Leave the meat in the fridge for at least one hour.
Place the meat on the indirect side and close the lid. Leave it until the inner temperature is 125° F, it takes roughly 45 minutes.
Now remove the lid, open all vents and crank up the heat. Once the fire is hot, place the meat back on the grill grates, still on the indirect side, close the lid and leave it until the inner temperature is 133-136° F.
Bring the meat inside. Slice it and serve with a creamy mash and some vegetables. The tangy lime flavor together with the black pepper and herbs will really make this lamb shine.