Xai Rostit

Remove the lamb from the refrigerator 1 hour before cooking to bring it to room temperature. Using a sharp knife, make 15-20 small deep incisions all over the lamb. Insert a garlic sliver and a small sprig of rosemary into each incision.

Rub the lamb all over with olive oil, salt, and pepper. If using, spread a thin layer of Dijon mustard over the surface. The mustard creates a beautiful crust and enhances the lamb's flavor without overpowering it.

Place the onion wedges in the bottom of a large roasting pan. Set the lamb on top of the onions, which will act as a natural rack and flavor the pan juices. Scatter the thyme sprigs around the lamb.

Roast at 220°C (430°F) for 20 minutes to develop a brown crust. Then reduce the temperature to 170°C (340°F) and pour the white wine around the lamb. Continue roasting for about 1 hour and 20 minutes for medium-rare, or until a meat thermometer reads 60°C (140°F).

About 45 minutes before the lamb is done, arrange the quartered potatoes around the lamb in the pan drippings. Turn them to coat with the flavorful juices. The potatoes should be golden and crispy by the time the lamb is ready.

Remove the lamb from the oven and transfer to a cutting board. Tent loosely with foil and rest for 20 minutes. This is essential; resting allows the juices to redistribute throughout the meat, ensuring every slice is moist.

While the lamb rests, return the potatoes to the oven to continue crisping. Strain the pan juices into a small saucepan, skim off excess fat, and simmer for 5 minutes to concentrate into a natural jus.

Carve the lamb into thick slices and arrange on a warm platter surrounded by the roasted potatoes and onions. Drizzle the natural jus over the sliced meat and serve immediately.