Rinse the lamb well under cold water and pat it very dry with paper towels.

Using a small knife, make 16 incisions across the skin side of the lamb leg, about 1 inch deep. Stuff each incision with ½ garlic clove and a small amount of rosemary.

Drizzle the lamb with olive oil and massage it evenly to coat. Generously season all over with kosher salt and black pepper.

For best results, place the lamb on a wire rack over a sheet pan and refrigerate uncovered for 6 hours to overnight.

Preheat your oven or Traeger Grill to 350°F. Transfer the lamb to a large roasting tray.

In a separate bowl, combine chicken broth, white wine (if using), lemon juice, mustard, and oregano, then whisk. Pour the mixture around the lamb, cover with wet parchment paper, and seal tightly with aluminum foil.

Cook for about 3.5 hours or until the lamb is very tender. If necessary, continue cooking until it is fork-tender.

After the time’s up, remove foil and parchment, and baste the lamb with the broth mixture. Add potatoes to the roasting pan and toss to coat in the juices.

Raise the heat to 425°F and cook for another 35 minutes until the lamb is browned and the potatoes are fork-tender. Serve once the lamb has rested for 10 minutes.