Do I cook lamb with netting on?

No. For even cooking, you must first remove the net and follow my instructions to flatten the meat, then roll it into a cylinder to get the best results.

How much boneless leg of lamb per person?

I usually serve ¾ lbs per person, about 2 slices each.

Should you cover lamb with foil when roasting?

No, there is no need. You want the oven air to circulate evenly around the meat for a nice sear on the outside.

Roasted Boneless Leg of Lamb with Garlic and Rosemary

Served with a bright and herby mint chimichurri, this leg of lamb roast recipe is a showstopper whether you serve it for Easter dinner, Christmas, or a special Sunday dinner.

If you’re looking for more roasted lamb recipes, we also have a roasted rack of lamb that is incredibly tender and has a well-rounded flavor profile through plenty of fresh garlic and rosemary.

Sliced roasted boneless leg of lamb served with mint chimichurri.

Ingredients and Substitutions for Leg of Lamb Roast
How to Cook Boneless Leg of Lamb in the Oven
Ideal Temperature and Cooking Time (Based on Doneness Level)
Expert Tips
How To Make Ahead, Store, Freeze, and Reheat
FAQs
What To Serve with It?
Other Lamb Recipes You Might Like:
Roasted Boneless Leg of Lamb Recipe

Ingredients and Substitutions for Leg of Lamb Roast

With a few simple ingredients—all of which you can find on a single supermarket run!—you can make this boneless leg of lamb roast recipe and wow everyone at your table. Here’s what you will need:

Ingredients for the recipe from the top view.

Boneless (or deboned) leg of lamb: Here in the U.S., you’ll typically find lamb from New Zealand, Australia, or the U.S. I usually buy mine from Costco, which carries Australian lamb leg. It is sold in different weights, so choose one based on how many people you plan on serving. The leg of lamb without bone I’m using here is just over 5 pounds, which is perfect for 6 to 8 adults, but you can go smaller or larger depending on your needs.
Dijon mustard: Dijon adds a nice tangy flavor and helps tame the gameness of lamb. I do not recommend swapping it out for yellow or brown mustard, which can be too harsh for this simple leg of lamb recipe.
Extra Virgin Olive oil
Fresh garlic cloves: We use a lot of fresh garlic in this recipe to balance out the gamey flavor of the boneless lamb roast—8 whole garlic cloves! You will use 4 of them, finely minced, for the inside of the lamb (mixed into the marinade), and the remaining four cloves will be stuffed into slits on the outside once it’s rolled.
Fresh herbs: We used a combination of fresh rosemary and parsley, though you’re welcome to substitute in thyme, as well. However, it’s important to finely mince the rosemary, if that’s what you plan on using, so the pine-like needles blend in well.
Spices and seasonings: This rosemary and garlic lamb roast is quite adaptable to a range of seasoning blends, depending on the flavor profile you’re aiming for. As a nod to my own Mediterranean roots, I opted for ground cumin and coriander.
Lemon zest: The brightness of lemon mellows out the gamey flavor in our seasoned leg of lamb.

How to Cook Boneless Leg of Lamb in the Oven

If you’ve been feeling a little intimidated when you see photos of perfectly roasted lamb, don’t worry—if you follow these simple steps that I’ve outlined for you, accompanied by the step-by-step photos, you can easily achieve a stunning roast boneless leg of lamb of your own. Here, my friends, is the best way to cook a boneless leg of lamb:

Prep your oven: Adjust your oven rack to the lower-middle position and heat the oven to 425 degrees F. (218 C). Place a wire rack on a baking sheet and set it aside to warm with the oven.

Steps showing how to make the seasoning and prep the lamb for the recipe.

Make the seasoning: Into a medium-sized bowl, combine your Dijon mustard, olive oil, 4 cloves of minced garlic, finely chopped fresh rosemary, finely chopped fresh parsley, ground cumin, ground coriander, Kosher salt, black pepper, and zest of a lemon. Stir mixture evenly.
Prepare the lamb: Remove the lamb from its packaging. It will likely look like an uneven bundle of meat. Lay it flat on a cutting board with the inside facing up. Do your best to spread it out into as even of a shape as possible. Pat it dry with paper towels on both sides to remove excess moisture. Using a sharp chef’s knife, trim off any excess fat, focusing on removing any greyish or tough fat. *Note: the grey fat is what brings out the gamey flavor, which is why we focus on removing that type in this step.
Remove the excess fat (optional): Turn it over and trim away any thick or uneven patches of fat, leaving a thin layer for flavor and moisture retention.

Steps showing how to prepare the boneless leg of lamb for roasting.

Even out the thickness: Flip the meat back to the inside facing up position. Cover the meat with plastic wrap. Using a meat mallet, gently pound the meat to create an even thickness of about 1-inch, focusing on the thicker areas. Remove the stretch film.
Spread it with the seasoning rub: Spread ⅔ of the Dijon-herb mixture evenly over the inside layer of the meat.
Roll into a cylinder: To roll the leg of lamb, begin with the right bottom part of the meat and roll it towards the center (away from your body), pulling it snug as you go. Then, take the left top side and roll it towards you, meeting the first roll in the middle. It should have a uniform cylinder shape. Tuck the ends of the meat inside the roll as much as you can.
Tie the lamb: Using butcher’s twine, secure the roast by tying loops around it at roughly 1 ½ inch intervals, ideally starting from the center and working towards both ends. You’ll likely need about 8-9 loops to keep everything in place. It doesn’t have to be perfect!

Person inserting sliced garlic in the lamb and seasoning the outside.

Cut small slits for more garlic: Using a pairing knife cut 14-16 1-inch slits evenly around the exterior of the lamb and insert the leftover four sliced garlic cloves into each cut as evenly as you can.
Season the outside: Spread the rest of the dijon-herb mixture over the outside of the deboned lamb roast, ensuring that all sides are evenly coated.
Roast: Transfer the meat onto the prepared baking sheet from the oven. Bake for 15 minutes in the preheated 425 degrees F oven for a nice sear and then turn the heat down to 350 degrees F and bake until the internal temperature reaches 125-130 degrees F (for medium-rare) when a thermometer is inserted in the middle of the roast. This takes about 40-45 minutes* (a total of 1 hour in the oven).
Let lamb rest: When the leg of lamb is finished roasting, remove it from the oven, tent it with foil, and let it rest for 10-15 minutes. As the lamb rests, the internal temperature will increase by 5 to 10 degrees, thanks to the residual heat.
Slice and serve: Transfer the roast onto a cutting board, remove the twine, and slice it into about 1-inch thick slices, depending on your preference. Transfer your boneless leg of lamb roast onto a plate and serve it with your favorite sauce (I served mine with my mint chimichurri sauce).

Boneless leg of lamb roast sliced and served with mint sauce on the side.

Ideal Temperature and Cooking Time (Based on Doneness Level)

Some of the top questions I receive are: How long to cook boneless leg of lamb? and What is the optimum cooking temperature? I promised you an easy boneless leg of lamb recipe, so here are a few notes to keep it easy & foolproof:

How long to roast a boneless leg of lamb depends on the weight and your preferred doneness level. While most boneless leg of lamb recipes say the cooking time per pound is about 15-20 minutes, I think it is more like 10-15 minutes.
3 things affect the boneless leg of lamb roasting time:
- The boneless leg of lamb temperature (I usually take the meat out of the fridge to come to room temperature for at least 30 minutes to an hour before working with it);
- The weight of your boneless lamb leg roast
- Your preferred doneness (rare, medium-rare, or medium).
The two-step process – My approach to roasting lamb starts with a high-heat sear to lock in flavor, followed by a slow, gentle cook. I begin at 425°F for the first 15 minutes, then lower the temperature to 350°F to ensure a tender, evenly cooked roast. The final touch happens as the lamb rests, allowing residual heat to finish the cooking process while keeping it juicy and flavorful.
Looking for a boneless leg of lamb roasting chart based on doneness? The below chart from America’s Test Kitchen cookbook, Meat Illustrated (affiliate link), is the one I use.

Desired Doneness	Cooking Stop Temperature	Final Temperature After Resting
Rare	115 to 120 °F (46 – 49 °C)	120 to 125 °F (49 – 52 °C)
Medium-Rare	120 to 125 °F (49 – 52 °C)	125 to 130 °F (52 – 54 °C)
Medium	130 to 135 °F (52 – 57 °C)	135 to 140 °F (57 – 60 °C)
Medium-Well	140 to 145 °F (60 – 63 °C)	145 to 150 °F (63 – 66 °C)
Well-Done	150 to 155 °F (66 – 68 °C)	155 to 160 °F (68 – 71 °C)

Residual heat will likely raise the temperature of your leg of lamb with garlic and rosemary by 5–10 degrees during the 10–15 minutes of resting. That means if I pull my lamb out when the internal temperature is at 120°F, it should ultimately reach around 130°F, which is exactly how I like it—perfectly tender and juicy.

Expert Tips

Here are a few tips from my foolproof test kitchen to help you get the best results on your first try:

Before cooking it in the oven, be sure to take it out of the refrigerator for at least 30 minutes to an hour prior. You do not want to put it directly in the oven while it’s still cold.
A wire rack is essential. A wire rack allows the air to circulate, producing an evenly cooked roasted leg of lamb. If you do not have a wire rack, you can use a roasting pan with a V-rack.
Chop your herbs finely. Rosemary is a pine-y shaped herb, and can add unpleasant bits to chew on if you don’t chop it finely enough. Feel free to experiment with the amount of herbs you use based on your preferences.
Remove the fat from the inside and outside of your leg of lamb in the prep stage. My boneless lamb roast recipe is perfectly flavored in large part due to this step, so don’t skip it. The grey fat on the inside is what contributes most to the gamey flavor of the lamb, so if that’s not something you enjoy (I do not), removing a large part of the grey fat will solve this issue. While the outer layer of fat does help retain moisture as it roasts, you want to remove some of it so the end slices are not excessively fatty.
Evening out the meat makes rolling your roast easier. This is a great tip that I picked up in my research from America’s Test Kitchen. Using a meat mallet (or you can also use a can or mason jar in a pinch) helps create an even layer, which then makes it easier to achieve the cylinder shape you see in my photos.
Do not skip resting your meat. Resting allows the juices to redistribute, making the meat extra tender.
Slice your baked boneless leg of lamb evenly. Using your chef’s knife to slice your roast into 1-1.5” slices will give you a beautiful presentation and equal serving sizes.