How to Roast a Boneless Leg of Lamb
Nothing could be easier than roasting a boneless leg of lamb for dinner.
Growing up, I remember Sunday dinners of roast leg lamb with roasted potatoes and mint jelly and eating the leftovers during the week. We roasted a lamb this week for dinner, had leftovers the next night, and I've been making sandwiches for the last couple of days.
What Is a Boneless Leg of Lamb?
A boneless leg of lamb is a cut of lamb meat that has had the bone removed, leaving just the lean meat. It is the same hind leg of a lamb as the bone-in leg of lamb, but it has been deboned either by the butcher or purchased as a pre-prepared cut.
It is a popular choice for those who prefer the convenience of easy carving and cooking without the presence of bones. It is typically sold rolled and tied with butcher's twine, creating a compact and uniform shape that ensures even cooking.
Since the bone has been removed, it may cook slightly faster than a bone-in leg of lamb of the same weight, and it can be easier to slice and serve. It is often used in various lamb recipes, such as roasting, grilling, or braising, and it can be seasoned and prepared in a similar manner to a bone-in leg of lamb.
While the boneless leg of lamb is convenient, some cooks and chefs argue that the bone-in version provides extra flavor and moisture during cooking due to the presence of the bone and marrow. However, boneless leg of lamb remains a popular choice for those who prioritize ease of preparation and serving convenience.
What are the advantages of a boneless leg of lamb?
A boneless leg of lamb offers several advantages that can make it a preferred choice for certain cooks and specific culinary situations. Here are some of the key advantages:
- Ease of Carving and Serving: One of the primary benefits of a boneless leg of lamb is that it is much easier to carve and serve than a bone-in leg. The absence of bones makes slicing the meat more straightforward, resulting in neater and more uniform portions.
- Faster Cooking Time: Since the bone has been removed, the cooking time for a boneless leg of lamb is generally shorter compared to a bone-in leg of the same weight. This can be advantageous if you want to prepare a meal more quickly.
- Consistent Cooking: The uniform shape of a boneless leg of lamb, often rolled and tied with butcher's twine, allows for more even cooking. This can lead to a more evenly cooked piece of meat with fewer variations in doneness throughout the lamb.
- Versatility in Cooking Methods: A boneless leg of lamb is versatile and well-suited for various cooking methods, such as roasting, grilling, pan-searing, and braising. The absence of bones does not limit your cooking options.
- Easier Seasoning and Stuffing: When the bone is removed, the inner cavity of the leg of lamb becomes accessible. This makes it easier to season the meat throughout or even stuff the lamb with herbs, spices, or other ingredients to infuse additional flavors.
- Reduced Carcass Weight: The boneless leg of lamb is sold based on the weight of the meat alone, whereas the bone-in leg of lamb includes the weight of the bone. This means you get more edible meat for the same weight as a bone-in cut.
- Convenience: For individuals who prefer the convenience of a ready-to-cook cut of meat without having to deal with bones, a boneless leg of lamb is an ideal option.
Ultimately, choosing between a boneless leg of lamb and a bone-in leg of lamb depends on personal preferences, cooking style, and the specific dish you intend to prepare. Both cuts have their advantages and can result in delicious and satisfying meals.
Buying a Leg of Lamb
There are three ways you can buy a leg of lamb, each with its advantages. There are more than these three cuts, but let's go with three for simplicity. By the way, even though a lamb has four legs, only the two back legs are referred to as the "leg of lamb."
Bone-in leg of lamb is usually a little cheaper, cooks faster than boneless, gives you a bone for making stock for lamb stew, and because the bone is a little juicier and has more flavor. A domestic leg of lamb weighs about 7 to 8 pounds.
A boneless leg of lamb with the bones removed is perfect for roasting and easy to carve. You can find it at your supermarket with the thin membrane (called fell) removed and the meat wrapped in a net to hold it together and keep its form.
Whether you buy the whole leg and have it boned or just the top half (sirloin half) or bottom half (shank half) depends on how many you serve and your personal preferences.
The sirloin half (consisting of the top of the leg and part of the hip) is meatier and more tender than the shank half (consisting of the lower leg), which is chewier because it has more connective tissue. However, when cooked properly, the connective tissue breaks down to be more tender and gelatinous with lots of flavor.
The butterflied leg of lamb is just a boneless leg that has been cut down the center in half but not entirely through. The halves are opened to lay flat, making the meat easier to grill or broil, but it can also be stuffed and rolled.
How Difficult Is It to Bone Out a Leg of Lamb?
Boning out a leg of lamb can be a moderately challenging task, especially if you're unfamiliar with butchery techniques or haven't deboned meat before. The process involves removing the bone from the leg of the lamb while keeping the meat intact and in good shape. It requires some skill, precision, and patience.
Here's a general outline of the steps involved in boning out a leg of lamb:
- Preparation: Place the leg of lamb on a clean cutting board with the bone side facing up. Ensure you have a sharp boning knife and a clean area to work.
- Trimming: Start by trimming any excess fat or connective tissue from the leg of the lamb. This will help you see the bone structure more clearly.
- Locating the Bone: Feel along the leg to locate the bone and identify its shape. It will be the largest central bone running through the leg.
- Cutting Around the Bone: Use the boning knife to carefully cut around the bone, separating the meat from the bone while keeping the knife as close to the bone as possible. You'll need to work your way around the entire bone, including the joint area.
- Removing the Bone: As you cut around the bone, gently pull and scrape the meat away from the bone until it's entirely separated from the meat. Be cautious not to cut through the meat or puncture the surface.
- Tying or Rolling: Once the bone is removed, you can choose to tie the meat back into its original shape using butcher's twine or roll and tie it into a roast for even cooking.
It's crucial to take your time and be patient during the process. If you're new to boning out meat, consider watching video tutorials or seeking guidance from a professional butcher to learn the proper techniques.
If you prefer not to bone out the leg of lamb yourself, you can always ask your local butcher to do it for you. They can provide you with a boneless leg of lamb ready for cooking, saving you time and effort.
American (Domestic), New Zealand, or Australian Lamb?
I will start by quoting The Complete Meat Cookbook by Bruce Aidells and Denis Kelly, "When it comes to flavor, tenderness, and overall quality, you can't beat lamb from the United States, especially California, Colorado, and Vermont."
Try to get it fresh, no matter what country you buy it from. A lot of the lamb from Australia and New Zealand is frozen, although more and more is coming over fresh. You will find the New Zealand and Australian lamb to be smaller and weigh less.
One of the significant differences between American lamb and "Down Under" lamb is diet. While the New Zealand and Australian lamb are raised almost exclusively on grass, American lamb is "finished" on a grain, which may be why the meat is milder.
I said roasting a leg of lamb is simple, but first, you have to decide what roasting method you want to follow. Everyone has their ideas on roasting meat these days.
Following Barbara Kafka's technique described in her informative Roasting - A Simple Art, you start at 500º F for 10 minutes, then lower heat to 425º F until the meat is at the desired temperature.
If you are a fan of Bruce Aidell and Denis Kelly in their Complete Meat Cookbook, you might roast the lamb at 350º F the entire time until the desired temperature.
, I like both these methods, but I'm also a fan of Julee Rosso & Sheila Lukins' The New Basics Cookbook. I broke my teeth on this book when I first started learning to cook, and I often refer to it as a reference. It is one of the most essential cookbooks you can own when starting out.
They give you all sorts of choices: bone in, bone out, high-heat, low-heat, stuffed, not stuffed, but we went with starting at 450ºF for 30 minutes and then reducing the heat to 375ºF until our desired internal temperature.
You really can't go just by time because there are so many factors that can affect the eventual temperature, including the weight of the meat you are cooking, how tightly it is tied, whether is it stuffed or not, how hot your oven is really cooking at, how long you let it rest - that kind of stuff.
What is the desired internal temperature?
Lamb is naturally tender, so you don't want to overcook it. Most chefs will tell you to cook and serve it rare. We like it more medium in our house, mainly when serving it to the kids.
If I were serving the lamb to guests who like it rare, I might pull it out rare, cut off a piece of the meat, and continue cooking the rest for a few more minutes until medium. The question is, what temperature is rare, medium-rare, and medium?
If you look through 10 different cookbooks, you may find ten different temperature ranges for each level of doneness. For example, The Complete Meat Cookbook says rare is 125º F to 130º F, medium-rare at 130º F to 140º F, and medium at 140º F to 150º F.
The New Basics Cookbook sees rare at 135º F to 140º F and medium at 150º F to 155º F.
And then there is the USDA Recommendation. They see rare at 140ºF, medium-rare at 150ºF, and medium at 160ºF. Most chefs would tell you an internal temperature of 160 is well done and too dry.
The answer is to experiment and determine the best temperature for you. Once you know that, you can cook it any way you want, knowing when to remove it from the oven.
Resting & Thermometers
Resting time is a mistake many home cooks make that affects the final temperature. As with all roasts, remove them about 5 degrees before reaching the desired ideal internal temperature. This allows the juices to be redistributed throughout the entire piece of meat.
As the meat rests, it will continue to cook about five more degrees, the juices will redistribute, and you will have a more flavorful, tender result. Never remove the meat from the oven and start carving. Give it a short and meaningful rest.
As for thermometers, they are all different, and if you have an old meat thermometer in your kitchen drawer for years, it may need to be recalibrated or thrown out and replaced.
We used our old meat thermometer and pulled the meat out at our desired temperature of 140ºF and then tested it with an instant thermometer to see that it read 150º F. After resting, it ended up at about 155ºF and was okay for us, but you can see how important it is that your thermometer is accurate. Then again, maybe my old thermometer was the accurate one. I'll have to test them in boiling water.
Roast Boneless Leg of Lamb
- 1 leg lamb boneless, about 4 to 5 lbs
- 2 tablespoons fresh rosemary
- 2 tablespoons fresh thyme
- 2 tablespoons fresh oregano
- 4 cloves garlic
- olive oil
- salt & pepper to taste
- Preheat the oven to 450º F.
- While the oven is heating, finely chop the herbs and garlic or use a food processor like we did.
- Rub some oil on all sides of the lamb and season with salt and pepper.
- Spoon the herb/garlic mixture on the topside of the lamb and spread it out.
- Place the lamb into a shallow roasting pan and roast for 30 minutes at 450ºF. Reduce the oven temperature to 375ºF and continue cooking until you reach the desired doneness as discussed above.
- Let the roast rest for 5 to 10 minutes until the internal temperature reaches ideal temp.While the roast is resting, now is a great time to make some pan sauce. We poured the juices from the bottom of the roasting pan into a saucepan, added a cup of demi glace and some of the herbs that fell off the roast when removing the netting. Let the sauce reduce until it is thick enough to coat a spoon.Ideally you would strain the sauce before serving, but we usually don't and it tasted great. Chefs have told me that straining makes a big difference so I need to incorporate that technique into my repertoire.