Whole Roasted Leg of Lamb

steps

1. Make the brine: In the bowl of a food processor, combine thyme, rosemary, garlic, and onion. Process until finely minced.
2. Make the lamb: In a 6-quart pot, combine minced herbs, 8 cups tap water, red wine, salt, peppercorns, pepper flakes, and bay leaves. Bring to a boil. Reduce heat to low and simmer, uncovered, for 20 minutes. In a food-safe vessel (4 gallons or larger), add hot brine and enough ice water (about a gallon) to get exactly 3 gallons of liquid. Stir liquid, then place lamb leg in the brine. Cover and refrigerate for 24 hours, stirring halfway through.
3. After 24 hours, remove lamb from brine and pat dry. Leave out for 2 hours to let lamb come to room temperature. Preheat oven to 400 degrees. With a boning knife, make twenty incisions a couple inches apart up and down leg, all the way to the bone. (Incisions should be large enough that you can put a finger in each hole.) Put approximately a clove’s worth of minced garlic in each hole. Rub lamb leg with oil, salt, and black pepper.
4. Take the large flap of flesh and skin from the bottom and fold it over to the ball in the joint of the leg (making it look like a uniform piece of meat). Wrap and tie it in place with butcher’s twine. 
On a rimmed baking sheet or casserole dish large enough to accommodate the lamb leg, place the leg cut side up (the exposed part; if it were untrussed, you’d be looking at the ball of the joint).
5. Roast for 45 minutes. Flip leg and roast for another hour, or until internal temperature reaches 135 degrees. Turn oven off, but leave lamb inside for another 15 minutes. This allows for a hot rest—the meat will be rested and cooked evenly throughout, but will still be warm when you serve it.
6. To serve, slice ¼-inch slices perpendicular to the bone, like a spiral ham, cutting against the grain. The thinner the slice, the more tender the lamb
 will be.

From A Cajun Christmas