Leg of Lamb with Roasted Garlic and Mint

2 medium heads garlic
3 Tbsp. EVOO, divided
2 Tbsp. fresh rosemary
2 Tbsp. fresh mint
1 Tbsp. balsamic vinegar
1-1/2 tsp. kosher salt
1/2 tsp. fresh ground black pepper

1 boneless leg of lamb, 3 to 3-1/2 lbs, butterflied

1. To make the paste: Remove the loose papery skin from the heads of garlic.  Using a sharp knife, cut about 1/2 inch off the top to expose the cloves.  Place each garlic head on a large square of heavy duty aluminum foil and drizzle 1 Tbsp. of olive oil over the top of the cloves. Fold up the foil sides and seal to make a packet, leaving a little room for the expansion of steam.  Grill over Indirect Medium heat until the garlic cloves are soft, 45 minutes to 1 hour.  When cool enough to handle, squeeze out the garlic cloves into a medium bowl.  Add the remaining ingredients, except the lamb.  Using the back of a fork or a mortar and pestle, thoroughly combine the ingredients to create a paste.

2. Carefully remove an excess fat and sinew from both sides of the lamb and lay it, skin side down on a flat surface.  It should be 1 to 1-1/2 inches thick.  Spread half the paste over one side of the lamb and tightly roll into a long cylinder.  Using twine tie the lamb at 2 inch intervals.  trim off loose ends of the twine.  Spread half of the paste over the outside of the lamb.  If not grilling immediately, cover and refrigerate.  Allow the lamb to stand at room temperature 30-40 minutes before grilling.

3. Sear the lamb over dirct medium heat until brown on all sides, 10-15 minutes, turning as necessary.  Mve the lamb over Indirect Medium heat and continue grilling to desired doneness, 1 to 1-1/4 hours for medium rare.  Remove from the grill and let rest for 5-10  minutes.  Remove the twine.  Cut the lamb crosswise into 1/4 inch slices and serve warm.