Boneless leg of lamb is a flavorful and easy-to-prepare cut that makes a stunning centerpiece for a holiday dinner or other special occasion. One of my favorite things about preparing boneless leg of lamb is that you naturally end up with meat of different degrees of doneness – perfect when feeding a crowd!
What Is Butterflied Leg Of Lamb?
Boneless leg of lamb is also sometimes referred to as a butterflied leg of lamb. What this means is that the bone has been removed from the leg and the meat has been cut in half so that it opens up more or less flat. I say more or less flat because some parts are still thicker than others. More on that below.
Grocery stores and butchers typically sell boneless (or butterflied) leg of lamb rolled up, tied, and held closed with a mesh netting. Also, you can purchase either a whole boneless leg of lamb, which weighs around 5 pounds, or a “short” boneless leg of lamb which will weigh between 3 and 4 pounds. If we follow the usual guidelines of allowing for 1/2 pound of meat per person, you can see that even the “short” leg of lamb feeds between 6 and 8 people.
Both oven-roasting and grilling are good methods for cooking a boneless leg of lamb. Whichever method you choose, consider seasoning or marinating the lamb in advance for maximum flavor.
How To Roast It
Here’s a fun fact! It will typically take longer to roast a boneless leg of lamb than a leg of lamb with the bone still in, even though the bone-in leg weighs more.
Why? It’s because the bone acts as a conductor to help spread the heat through the meat. Put another way, meat that is touching bone cooks quicker than meat that is touching just meat. Who knew?
To roast boneless leg of lamb in the oven, you first need to remove the mesh netting. At this point, you have two choices. One, simply leave the boneless leg of lamb tied up and season the outside before roasting. This is the easiest method and perfect for when you are in a rush.
But, if you are willing to do a little more work, you can also untie the roast, open it up, and season both sides before rolling it back up and tying it closed for cooking. This second method is my preference because it’s very easy to roll and tie the meat yourself and you can add so much flavor by seasoning both sides of the meat with herbs and spices.
If you are going to the trouble of untying and opening up the roast, I highly recommend seasoning the lamb in advance with a rub or marinade and letting it rest in the refrigerator for several hours or even overnight. This will give your roast so much flavor and the meat will come out especially tender and juicy.
The recipe below includes a garlic and herb rub that incorporates classic Greek flavors like parsley, lemon, and oregano – all of which pair exceptionally well with lamb.
To roast the boneless leg of lamb, start with a screaming hot oven to give the meat a nicely browned crust on the outside. Then, after about 30 minutes or so, turn the heat down and let the inside of the roast cook more slowly until done.
You want to take the roast out when the center reaches 130 to 135° Fahrenheit on a meat thermometer (like this one). The meat will continue to cook as it rests, so taking it out when the center is around 130° will ensure nice, pink, medium-rare meat in the center of the roast.
For those folks who prefer their meat medium, the outer slices will be more cooked than the inside, so there will be something for everyone. As always, carve the roast by slicing against the grain.
How To Grill It
For grilling, it is best to untie the lamb and grill it flat. As I mentioned above, when it is opened up flat, there are thinner and thicker parts of the butterflied leg of lamb.
If you know that you are serving some people who like their meat more well done and others who like it rarer, you can go ahead and grill the lamb as-is and aim for medium-rare for the thickest part of the lamb. That way, the thinner parts will end up well done and everyone can have the part they like.
Alternatively, if you want to cook the butterflied leg of lamb more evenly, you can cut into the thickest part of the meat from the center, but don’t cut it all the way through. Then you should be able to open up that thicker piece like a book and the whole leg will lay flat and be more even in thickness.
As with roasting, marinating the boneless leg of lamb before grilling is a great way to add flavor. Many different ingredients work well with lamb, including yogurt, soy sauce, citrus, pesto or other herb pastes, and olive tapenade. Grilled lamb is a dish found in cuisines from Greece to India to the Middle East, so be creative!
Grill butterflied leg of lamb over direct, medium-high heat. Start the meat by placing it fat-side down on a preheated oiled grill. Grill until the internal temperature reads 130 to 135° Fahrenheit in the thickest part, about 10 to 15 minutes per side.
If the lamb is starting to char, turn the heat down to medium or move the lamb to a cooler part of the grill. Let the meat rest for 10 minutes prior to carving.
Whether you grill it flat or roast it rolled up and tied, boneless leg of lamb is an exceptionally versatile, flavorful, and crowd-pleasing cut of meat. Be sure to give it a try for your next holiday meal, dinner party, or backyard cookout.Print
- 1 lemon
- 6 cloves garlic, peeled
- 1 cup loosely packed flat-leaf parsley leaves
- 1/2 cup loosely packed oregano leaves
- 1 tsp. kosher salt plus more for seasoning
- 1 tsp. freshly ground black pepper plus more for seasoning
- 3 Tbsp. extra-virgin olive oil
- 3–4 lbs. boneless leg of lamb
- Zest and juice the lemon.
- Combine the garlic, parsley, oregano, lemon zest, 2 tablespoons of the lemon juice, salt, and pepper in the bowl of a food processor and pulse a few times to combine.
- With the motor running, slowly pour in the olive oil in a steady stream and process until the mixture forms a coarse paste. Set aside.
- Unwrap the leg of lamb and remove the mesh netting, if there is one. Lay the lamb flat on your work surface with the inside of the leg of lamb facing up. (That is the side without the cap of fat and where the bone used to be.)
- Spread approximately ⅔ of the garlic-herb rub on the inside of the leg of lamb.
- Cut three long pieces of kitchen twine and have them handy.
- Starting with one of the short sides, roll the lamb up tightly with the garlic-herb rub on the inside.
- Tie the lamb using the twine at 2-inch intervals to keep it closed.
- Use additional pieces of twine as needed to keep the roast together.
- Rub the remaining garlic-herb mixture on the outside of the lamb.
- Place the lamb in a baking dish or on a plate and cover it. Refrigerate the lamb for at least one hour and up to overnight.
- When ready to cook, remove the lamb from the refrigerator and bring it up to room temperature.
- Preheat the oven to 450°F.
- Place the lamb in a roasting pan that fits it snugly and season the outside with a sprinkle of salt and pepper.
- Roast the lamb at 450°F for 30 minutes. Then turn the heat down to 375°F and rotate the roasting pan 180°.
- Continue roasting the lamb until an instant-read thermometer (like this one) inserted into the thickest part reads 125 to 130°F for medium-rare, an additional 30 to 45 minutes.
- Allow the lamb to rest for 10 minutes prior to carving. The temperature of the meat will continue to rise another 10 to 15 degrees as it rests.
- Carve the lamb across the grain into thin slices. Serve immediately.