How To Roast a Leg of Lamb
You can have the turkey. Leave the ham. Prime rib — what’s that? In my house, leg of lamb is the celebratory roast; I love its tenderness and flavor.
Have you ever roasted a leg of lamb? It may sound intimidating, but the sweet little secret is that leg of lamb is actually one of the easiest, most foolproof cuts of meat to cook. Here’s our remarkably simple, fuss-free approach to cooking a leg of lamb. It will turn out perfectly every time.
Expert Tips for Buying & Cooking a Leg of Lamb
While I’ve cooked lamb on many occasions, cooking a whole leg can still feel intimidating. It’s a large, expensive cut of meat, and I always wonder whether I am going to dry it out or make it tough. Should I marinate it? Should I do something special to make sure it’s cooked properly?
I spoke to my favorite local butcher, Bluescreek Farm Meats, in Columbus, Ohio, to learn a little more about leg of lamb and how to cook it.
Here are some expert tips from Jamie Smith at Bluescreek on what to look for in lamb, and how to cook it. A sneak peek: Cooking a leg of lamb is actually really, really simple.
What Is a Leg of Lamb?
When we talk about lamb leg, we mean one of the back haunches of the animal, and the most common cut includes the upper part of the leg only. (Think of the thigh, without the lower part of the leg.)
Shank On or Off?
Usually leg of lamb is sold without the shank attached; you are just buying the upper part of the leg, as seen here, without the lower part. You can order a leg of lamb with the shank left on, however; this is sometimes called an “American leg,” but usually it’s simply referred to as “shank-on leg.”
Some people prefer this, as it looks more traditional and dramatic on a serving platter, but there’s no major advantage to having the shank (other than getting an extra soup bone!).
Boneless or Bone-In?
Jamie prefers bone-in, for the flavor. Think of how we make stock from bones, she said. The bones hold so much of the flavor. When you roast a piece of meat with the bone still in, you are getting all that flavor in the meat itself. A bone-in lamb leg can be a little trickier to carve, but we opted for bone-in in this cooking lesson (we’ll show you how to carve it).
If you are really nervous about carving meat, boneless is fine; it’s easier to slice. If you buy a boneless leg of lamb, it will probably come in a net. When the bone is removed from the lamb, the meat needs to be held together in the shape of the leg for cooking, so heatproof, oven-safe netting is usually used. If your netting isn’t oven-safe, you can tie it up with kitchen twine instead (or ask your butcher to do it for you!).
What Should I Ask for at the Butcher?
When buying a leg of lamb we recommend doing so from a quality and reputable butcher. A leg of lamb is expensive regardless of where you buy it, so we feel that the investment is best spent with a butcher who either raises the animals himself (as Bluescreek does on their farm) or who can tell you how the lambs were raised.
We look for lambs that are market weight, which means no baby lambs, and no lambs that are too old and verging on (tougher) mutton.
Also, ask the butcher if they can trim the lamb leg for you if they have not already done so. This means that they will trim away the fell, a thick outer layer of fat (which is what can make lamb taste so strongly “mutton-y”), as well as any additional fat that you request to have removed. Personally, I like a nice pad of fat, which insulates the meat and keeps it tender.
Should I Marinate a Leg of Lamb?
Now, how to cook your leg of lamb? Here’s where things get really interesting.
“Lamb leg is a really tender cut,” said Jamie at Bluescreek. “You don’t need to marinate it.” In fact, she said, marinating lamb can actually make it tougher. A marinade is designed to break down the tough fibers in meat, but since lamb is naturally so tender, marinating can destroy the integrity of the meat — the texture and flavor — and make it tough to chew. “I would not marinate a lamb leg for more than two or three hours,” said Jamie. “It’s fine to follow a recipe, but be cautious.”
To add flavor to the roast, we decided to skip marinating altogether and season it simply with herbs and garlic.
Rare, Medium, or Well?
Personal preference should determine how long you cook your leg of lamb. Personally, I find rare and bloody lamb to be unappetizing. I prefer medium-rare to medium — still tender, with a hint of pink. We calibrated our cooking lesson below to this stage of doneness, but consult the cooking chart below if you like your lamb done differently. I will say that such a large cut of meat will probably have some variability; parts of the lamb leg were a little closer to medium, and others were closer to rare.
Internal Temperatures for Bone-in Leg of Lamb
All of these cooking times take into account the fact that we broil the lamb first to sear it. They also assume a resting period of at least 15 minutes, during which the lamb actually continues cooking internally. It’s best, especially if you like rare or medium-rare lamb, to take it out at a lower temperature than those officially recommended by the USDA.
REMEMBER! These times are only guidelines. Depending on many factors, your lamb leg may roast slower or faster. Check after one hour and then continue roasting, checking frequently, until the lamb reaches your desired internal temperature.
Roasting Temperature: 325°F
- Rare: 125°F (about 15 minutes per pound)
- Medium-Rare: 130°F to 135°F (about 20 minutes per pound)
- Medium: 135°F to 140°F (about 25 minutes per pound)
- Well-Done: 155°F to 165°F (about 30 minutes per pound)
Lamb Is Already Tender: Don’t Overdo It!
The primary takeaway, said Jamie, is that lamb is already a really tender cut of meat. Cooking should be simple. And that’s what we’ll show you here: a simple, easy way to cook a tender and juicy leg of lamb every time.
A bone-in leg of lamb always surprises me with how easy it is to roast. This cut of lamb is always so flavorful, that just some garlic and rosemary is needed to flavor it. It may seem like a large piece of meat, but it’s great as a holiday table centerpiece or a hearty dinner on a weekend that leaves you with leftovers for sandwiches or salads for the week.
Carving a leg of lamb is actually easier than carving a whole chicken, so we’ve added some more photos to walk you through the whole process visually so that you have a beautiful serving platter of perfect lamb slices when you’re all done.
– Christine, November 2018
How To Roast a Leg of Lamb
Serves10, depending on size of the leg
Prep time: 15 minutes
Cooking time: 1 hour 30 minutes
(5 to 7 pound) bone-in leg of lamb
- 3 tablespoons
Freshly ground black pepper
- 6 cloves
Leaves from 3 fresh rosemary sprigs, coarsely chopped (about 1 tablespoon)
Roasting pan with rack
Sharp chef's knife or carving knife, for carving
Rub the lamb with olive oil and season with salt and pepper. Take the leg of lamb out of the refrigerator about an hour before cooking so it comes closer to room temperature. This promotes faster, more even cooking. Set the lamb in a rack inside a roasting pan. Drizzle with the olive oil and rub all over into the fat and meat. Season generously all over with salt and pepper. Position the lamb so that it is fat-side down.
Broil for 5 minutes. Arrange an oven rack so that the top of the lamb is a few inches from the broiler element. Heat the broiler. Broil until the surface of the lamb looks seared and browned, about 5 minutes.
Flip the lamb over and broil the other side. Flip the leg over and put back under the broiler until the other side is seared, about 5 minutes more.
Top with garlic and rosemary. Take the lamb out of the oven. Turn off the broiler and set the oven temperature to 325°F. Reposition the oven rack to the middle of the oven. Rub the top of the lamb with the garlic and rosemary.
Cover the lamb loosely with foil and roast 1 hour. Tent the pan loosely with aluminum foil to keep the garlic and rosemary from burning. Put the lamb back in the oven and roast for 1 hour.
Uncover and take the temperature. Uncover the lamb. Take its temperature with an instant-read thermometer in the thickest part not touching bone. The lamb is ready when the temperature is 135°F or above. At 135°F the lamb is cooked to rare, but it will continue cooking as it rests, so we recommend taking it out of the oven at 135°F for medium-rare to medium. (Refer to the cooking chart above for general roasting times.)
If the lamb is not ready, continue cooking uncovered until it reaches your desired internal temperature, checking the temperature every 20 minutes.
Figure out where to carve. Let the lamb rest for at least 15 minutes before carving. Transfer the lamb to a clean cutting board. The bone runs through the meat at an angle, giving you two fairly big pieces of meat on either side of the bone. Start with the side of meat that feels most accessible to you.
Cut the meat into slices across the grain. Make straight, parallel cuts straight down through the thickest part of the meat until you hit the bone. You should be cutting perpendicular to the bone, across the grain of the meat. The slices will still be attached where they meet the bone.
Cut the slices off the bone. Turn your knife so that it's now parallel to the bone instead of perpendicular. Starting at the end of the bone furthest from you, cut through the slices where they attach to the bone. Keep your knife close to the bone so you get as much meat as possible, but don't worry about getting every single scrap of meat right now — just focus on cutting cleanly through the big slices and you’ll get any leftover pieces later.
Transfer the slices to a serving platter. Place the slices on a serving platter. Tent the platter with foil to keep the meat warm.
To serve: We highly recommend serving the lamb with this mint pesto.
Storage: Leftover lamb can be refrigerated in an airtight container for up to 3 days.
Freezing: Jamie recommends freezing leftover rare to medium-rare lamb in slices wrapped in foil. Then, to warm them, she puts the frozen slices, still wrapped, in a 350°F oven. This will warm them and not overcook them.