Adapted from this recipe by Mario Batali.
For the lamb:
1 boneless leg of lamb, approx. 4 lbs
5 cloves garlic
1/2 cup mint leaves
For the lemon salad:
2 lemons, peeled and sliced into thin wedges
1 bag baby spinach, washed
1/4 - 1/3 cup extra-virgin olive oil
For the black olive pesto:
1/2 cup black olive paste
1/4 cup diced red onion (optional -- this adds some bitterness and heat)
1/4 cup pine nuts
2oz blanched almonds
1 clove garlic
1 pinch red pepper flakes
splash orange juice
juice of 1 lemon
Before firing up the grill, give yourself some time to prepare. The lamb should have time to come to room temperature, or nearly so, before it hits the grill, and the black olive pesto and components of the lemon salad need time to rest before being served. The black olive pesto can be made a day ahead. If you don't go that route, make it at least an hour before serving, as this will give time for the ingredients to marry, and for the bitterness from the red onion to subside (when onion is blended in the food processor, the cell walls break down and a series of complex chemical reactions begins to take place. These reactions cause the fumes which make you cry when you chop onions, and they cause an unpleasant bitterness when the cell walls are really ripped to shreds in the food processor.)
Wash, dry, and butterfly the lamb, and set it aside to come to room temperature. In the food processor, pulse together the garlic and mint, then add olive oil in a drizzle until the mixture reaches a thin paste consistency. Add salt and pepper. With a sharp knife, score the fat on the fat side of the lamb, then make 4-5 deep cuts into the meat side. Rub the garlic mint paste mixture all over the lamb and season thoroughly with salt and pepper.
To make the pesto, pulse the garlic clove in the processor, then add the nuts and red onion, and pulse again. Add the olive paste and pepper flakes, and pulse again, then begin adding the lemon juice, orange juice, and olive oil. Add the orange juice and olive oil to taste. Add salt (if necessary) and black pepper. Set aside.
To make the lemon salad, toss together the lemon wedges and olive oil in a large bowl, and season with salt and pepper. Let this mixture rest for at least 1/2 hour, and toss together with the spinach just before serving.
Begin grilling your lamb by searing it directly over very hot coals. If the fire flares up too high, shift the meat away from the flames, or squirt the flame directly with water. Cook until the outside is deeply browned with a little char, move it off the direct heat (to a part of the grill uncovered by coals) and close the lid of the barbecue to finish cooking. The meat is done (medium-rare) when it has reached an internal temperature of 125 degrees (it will rise in temperature considerably while it rests) This will take about half an hour, depending on the heat of the grill and the thickness of your lamb. Remove the meat to a platter and allow it to rest about 10 minutes -- during this time, the internal temperature will rise another 10 degrees.
To serve, toss together the spinach and the lemon/olive oil mixture. Place this salad on each plate, top with slices of lamb, and top the lamb slices with a dollop of the black olive pesto. Enjoy!