Slow Roasted Leg of Lamb with Orange-Rhubarb Glaze

For the Lamb and Spice Paste:

In a small bowl, whisk together the olive oil, lemon paste, and Ras el Hanout to make a paste.

Lay the lamb out on a board and score the fat. Then rub both sides of the leg with the kosher salt, massaging the salt into all the nooks and crannies. Do the same with the spice paste, covering all the meat and massaging the paste all over. Roll up the leg and tie it tightly with kitchen twine, tucking it into as firm a shape as you can manage. Place a rack on a sheet pan and put the leg on the rack. Cover loosely and refrigerate overnight.

When you are ready to cook the lamb, preheat the oven or grill to 250 degrees F. Remove the lamb from the refrigerator and place it on a sheet pan in the oven or directly on the grill. While the lamb is roasting, make the glaze.

For the Glaze: In a small saucepan, combine the rhubarb, brown sugar and water. Simmer for 10 minutes until the rhubarb is soft and jammy. Remove from heat and add the spices, salt, balsamic vinegar and honey. Pulse with an immersion blender to liquefy. Add the orange zest and mint. Keep the glaze on a warming plate, below simmer, for 30 minutes as the lamb continues to cook.

Slow roast the lamb until the internal temperature reaches 120°F. Cooking time will vary and an internal thermometer is very helpful. When the roast reaches 120°F, quickly baste the leg with 1/4 cup of the glaze and continue cooking until the internal temperature reaches 125°F. Remove the lamb from heat and allow to rest 10-15 minutes until the internal temperature reaches 130°F for medium rare. Allow to rest 10-15 minutes and transfer to a large board. 

Carve the meat and arrange on a platter, basting all the cuts generously with the sauce. Serve additional sauce alongside.