Grab two springs of rosemary from your bunch and strip the leaves off using your hands. Set one spring aside and finely chop the other bunch.
With a sharp knife make a series of cuts throughout the lamb around 1 inch apart, around 1/2 inch deep. Make sure to get the bottom & sides but mainly focus on the top side.
Once cut all over insert olives, garlic, and leftover whole rosemary leaves into the holes. For best results add one piece per hole.
Cover the lamb all over with oil from the spray bottle, to get an even cover give the lamb a good rub. Combine herbs de Provence, peppercorns, chopped rosemary & salt and sprinkle over the lamb. Be sure to give the seasoning a light pat down to make sure it sticks to the oil.
For this recipe, I am using a charcoal grill. You need to set up your charcoal grill for indirect grilling and preheat to a medium heat. Set your drip pan in the center.
Once your grill has come to temperature, place half of your wood chips on the coals and place your lamb on the grate. Place the lamb away from the heat and cover with aluminum foil. Baste every 30 minutes with olive oil. For best results use a sprig of rosemary for basing.
Around 1 hour into the cook it will be time to add more coals and wood chips. Add a further 1/2 cup wood chips and 12 fresh coals to your grill, this should be plenty for medium rare and well done.
Grill lamb until cooked to your taste. My favorite is medium rare, this usually takes around 1-1/2 to 2 hours.
Transfer your leg of lamb to a chopping board, cover and let rest for 10 minutes.
Carve, serve and enjoy!