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Slow-Roasted Leg of Lamb

Roasted Leg Of Lamb

This slow-roasted bone-in leg of lamb is garlicky, rosemary-scented, and fall-apart tender with a rich pan gravy made from the roast juices. It cooks low-and-slow for about 3 hours and can be prepped ahead, making it an ideal holiday or dinner centerpiece.
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Prep Time:30 minutes
Cook Time:3 minutes
Total Time:4 minutes

Equipment

  • cutting board
  • paper towels
  • large roasting pan
  • aluminum foil
  • gravy fat separator
  • large freezer bag
  • 3+ cup liquid measuring cup
  • large saucepan
  • whisk
  • tongs

Ingredients

  • 5-7 lb. leg of lamb center cut roast bone-in
  • 1 whole head garlic unpeeled, cut in half horizontally
  • 2 yellow onions unpeeled, cut in half horizontally
  • 4 cups reduced sodium beef broth
  • 2 cups water
  • 6 cloves garlic minced
  • 2 tablespoons olive oil
  • 1 1/2 tablespoons kosher salt
  • 1 tablespoon Dijon mustard
  • 1 tablespoon pure maple syrup may sub brown sugar
  • 1 tablespoon lemon zest
  • 1 tablespoon rosemary minced, fresh
  • 1 1/2 teaspoons chili powder
  • 1 tsp paprika, pepper each
  • 1/2 tsp dried thyme, dried oregano, onion powder each
  • 5 tablespoons unsalted butter
  • 1/3 cup flour
  • reduced sodium beef broth as needed (will use mostly pan juices)

Instructions

  1. Remove the lamb from its packaging and place it on a cutting board. Pat the entire roast completely dry with paper towels.
  2. Let the lamb sit at room temperature for 60 minutes while you trim, score, prep the pan, and make the wet rub.
  3. Trim excess fat so the fat cap is about 1/8-inch thick. Score the lamb on both sides in a crosshatch pattern with cuts about 1-inch apart and 1/4–1/2-inch deep.
  4. Preheat the oven to 325 degrees F. Place the halved yellow onions and the halved head of garlic, cut side up, in the center of a large roasting pan.
  5. Make the wet rub by combining the minced garlic, olive oil, kosher salt, Dijon mustard, pure maple syrup (or brown sugar), lemon zest, minced fresh rosemary, chili powder, paprika, pepper, dried thyme, dried oregano, and onion powder.
  6. While the lamb is still on the cutting board, rub half of the wet rub into the fat-cap side, massaging it into the scoring. Do not rub the other side yet.
  7. Place the lamb, seasoned side down, in the roasting pan so it is propped up on the garlic and onions. Use your hands to rub the remaining wet rub all over the lamb.
  8. Pour the 4 cups reduced sodium beef broth and 2 cups water (or specified liquid) around the lamb in the pan, then cover the pan tightly with foil.
  9. Bake at 325 degrees F for 3 hours. After 3 hours, check with tongs to see if the meat easily pulls from the bone; if not, continue roasting until the lamb is tender.
  10. Remove the lamb from the oven and generous spoon pan juices over the roast. Transfer the lamb to a serving platter and cover loosely with foil while you make the gravy.
  11. Remove the onions and garlic from the pan juices. Pour the pan juices into a gravy fat separator cup and skim off the fat as you pour.
  12. If you don't have a fat separator, pour the pan juices into a large freezer bag, let the fat rise to the top, then cut a small corner of the bag over a 3+ cup liquid measuring cup to drain the de-fatted juices from the bottom.
  13. Add the de-fatted pan juices to a 3+ cup liquid measuring cup and add additional reduced sodium beef broth only if needed to equal 2 1/2 cups of liquid; set this aside.
  14. Melt the unsalted butter in a large saucepan over medium heat. Add the flour and cook, whisking constantly, for 2 minutes to make a roux.
  15. Reduce heat to low and slowly whisk in the 2 1/2 cups of pan juices/broth. Bring to a simmer, whisking constantly, until the gravy thickens to the desired consistency. If it becomes too thick, whisk in additional broth.
  16. Taste the gravy and season with salt and pepper to taste. The recipe suggests starting with beef bouillon, 1/4 teaspoon at a time, before adding more salt.
  17. Remove the meat from the bone with tongs and top with the prepared gravy.

Notes

Prep Ahead:This leg of lamb roast is ideal to prep ahead of time. Prepare the recipe through rubbing the wet rub all over the lamb. Loosely tent with foil for up to 24 hours. Remove the leg of lamb from the fridge 60 minutes before cooking and then proceed with the recipe.
Storage:Leftover leg of lamb roast can be stored in an airtight container in the fridge for up to 5 days or in the freezer for up to 3 months.
To reheat:To microwave, reheat portions for 60 seconds, followed by 10-second intervals as needed. To reheat in the oven, transfer pulled lamb to foil and enclose with a splash of broth or water. Bake at 350ºF for 8-10 minutes or until warmed through. To reheat in a skillet, add pulled lamb to a skillet with a splash of water or broth. Cover and cook on low until warmed through, stirring occasionally.