01 - Set the oven to 400°F.
02 - Pat the leg of lamb dry and rub with 2 tablespoons olive oil, 2 teaspoons sea salt, 1 teaspoon black pepper, 1 tablespoon chopped rosemary, and 1 tablespoon thyme leaves.
03 - Toss potatoes, carrots, onion, and garlic in a large roasting pan with the remaining 1 tablespoon olive oil, a pinch of salt, and black pepper.
04 - Place the seasoned lamb on top of the vegetables in the roasting pan.
05 - Pour 1 cup of low-sodium broth into the bottom of the pan.
06 - Roast uncovered at 400°F for 1 hour.
07 - Reduce oven to 350°F, baste the lamb with pan juices, and roast for an additional 30 to 45 minutes until the internal temperature reaches 140°F for medium-rare.
08 - Remove lamb and vegetables from oven, tent lamb with foil, and let rest for 15 minutes before carving.
09 - Slice lamb and serve with roasted potatoes, carrots, onion, and pan juices. Garnish with lemon wedges if desired.