Leg Of Lamb Recipe

Bring to room temperature

Remove the leg of lamb from the refrigerator 1 to 1.5 hours before cooking so it comes to near room temperature. Pat dry with paper towels.

Prepare garlic and herb paste

In a small food processor or using a knife and bowl, combine garlic cloves, chopped rosemary, chopped thyme, lemon zest, lemon juice, Dijon mustard, kosher salt, and black pepper. Pulse or mince until a coarse paste forms. Slowly drizzle in the 4 tbs olive oil while pulsing to create a spreadable marinade.

Score and season the lamb

Place the leg on a board fat-side up. Using a sharp knife, make shallow 1 cm incisions across the fat in a crosshatch pattern. Rub the herb-garlic paste all over the leg, forcing some paste into the incisions. If time allows, tuck remaining herb mixture under the fat or tie the leg back up. Let rest for 30 minutes (or refrigerate covered for up to 8 hours) to allow flavors to penetrate.

Preheat oven

Preheat the oven to 220°C (425°F) for 15 minutes with a rack in the middle position. If using a roasting pan with a rack, position the rack inside the pan.

Sear (optional but recommended)

Heat a large ovenproof skillet or roasting pan over medium-high heat. Add 1 tablespoon of olive oil. When shimmering, place the leg fat-side down and sear 3–4 minutes until well browned. Turn and sear other sides for 2–3 minutes to develop color. Remove to the rack in the roasting pan, fat-side up.

Roast

Place the lamb in the preheated oven and roast at 220°C (425°F) for 15 minutes to set the crust. After 15 minutes, reduce oven temperature to 180°C (350°F) and continue roasting. Roast times (approximate) from refrigerator temperature: 20 minutes per 500 g for medium-rare, 25 minutes per 500 g for medium. For a 2 kg leg: roast approximately 80 minutes total (including the initial 15), checking internal temperature after about 60 minutes. Aim for internal temperatures: 55–57°C (131–135°F) for medium-rare, 60–63°C (140–145°F) for medium. Use an instant-read thermometer inserted into the thickest part, not touching bone.

Rest the meat

When the lamb reaches your target temperature, remove from oven and transfer to a cutting board. Tent loosely with foil and rest 20–25 minutes. Resting allows juices to redistribute and carryover cooking will raise internal temp a few degrees.

Make pan sauce (optional)

While the lamb rests, put the roasting pan (or searing skillet) on the stovetop over medium heat. If pan has excess fat, spoon off all but about 1 tbs. Add the red wine (120 ml) to deglaze, scraping browned bits from the bottom with a wooden spoon. Simmer until reduced by half (2–4 minutes). Add the beef or lamb stock (240 ml) and simmer until sauce thickens slightly, about 6–8 minutes. Off heat, whisk in the cold butter 1 tbs at a time to finish and give shine. Taste and season with salt and pepper as needed. Strain if you want a smooth sauce.

Carve and serve

Remove twine if used. Using a sharp carving knife, cut the leg into 1 cm thick slices across the grain. Arrange on a warmed platter, spoon pan sauce over slices or serve on the side.

While the lamb is coming to room temperature, prepare vegetables: place carrots, onion quarters, celery pieces, and potatoes in a large bowl. Toss with 2 tbs olive oil, 1 tsp salt and 1 tsp pepper until evenly coated.

Scatter vegetables in an even layer in the bottom of the roasting pan (under the rack if using). They will roast in the lamb juices and become caramelized. If you seared the lamb in the same pan, you can add vegetables after searing to catch the fond.

Roast together with the lamb. Check vegetables after 40 minutes; turn if necessary for even browning. If they are done earlier than the lamb, remove and keep warm. If still firm when lamb is finished, you can increase oven temperature to 200°C (400°F) for the last 10 minutes to caramelize.

Serve vegetables alongside carved slices of lamb, spooning any pan juices over them.