-
Preheat the oven to 450F/220C.
-
Using a mortar and pestle, pound the garlic, allspice berries, and peppercorns with a little salt, in increments if necessary, until the mixture is a damp, chunky paste. Mix together with the grated cheese. Set the mixture aside until ready to use.
-
Rinse and pat dry the lamb. Using a sharp paring knife, make about 25 incisions on all sides of the lamb. Take a large pinch of the cheese-garlic-spice mixture and stuff it into each of the incisions, as deeply as possible. Continue until the mixture is used up, making additional incisions if necessary.
-
Rub olive oil over the surface of the lamb leg and season generously with salt and pepper.
-
Place the vegetables under and around the leg of lamb in the pan. Season with salt and pepper. Strew the herbs all around the vegetables and stick a few sprigs into some of the incisions in the meat, too. Drizzle everything generously with olive oil. Pour the red wine over and around the lamb.
-
Cover the pan with parchment or wax paper and seal with aluminum foil. Roast the lamb at 450F / 220 C for 20 minutes, then reduce heat to 350F/170C and continue to roast, basting every 15 to 20 minutes, for about 20 minutes per pound, or 2 to 2 ½ hours for medium-rare, or until a meat thermometer inserted into the thickest part of the leg reads 145F.
-
Ten minutes before removing from the oven, whisk together the finishing marinade and pour it over the lamb. Continue roasting another 6 to 8 minutes.
-
Remove and let the lamb rest for 20-30 minutes before carving.