A perfectly roasted boneless leg of lamb is a beautiful meal to serve for Easter, special occasions, and holidays. With this simple recipe, you can present an elegant cut of meat that’s tender and juicy with mouthwatering flavors of rosemary and garlic. If this is your first time making lamb, it won’t be your last!
If you are intimidated by lamb, don’t be. This is quite possibly one of the easiest and awe-inspiring recipes. Guests will marvel at how delicious it was, and you will be cool as a cucumber because it was so easy.
In fact, find all of the sides and fixings to round out your Easter Dinner Menu where the rest of my Easter recipes live. Don’t forget the deviled eggs and mashed potatoes! Those complete every Easter meal!
How to cook a boneless leg of lamb
Unlike most recipes for large cuts of meat, this one does not require any brining time. This leg of lamb just needs a simple herb rub that serves as a brief marinade right before it goes in the oven.
Which is better bone-in or boneless leg of lamb?
Bone-in leg of lamb is usually a little cheaper and cooks faster. Plus, you get a bone for making stock. The bone adds a little extra juiciness to the meat; however, boneless lamb roasts can be just as delicious and are much easier to carve without the bone.
Leg of Lamb Marinade Ingredients
- Lamb Roast
- 3 cloves garlic, minced
- 2 teaspoons fresh rosemary leaves, coarsely chopped (1 teaspoon dry rosemary leaves)
- 1/4 teaspoons ground black pepper
- 1/2 cup olive oil, extra-virgin
- 2 tablespoons lemon juice, fresh-squeezed
This recipe uses a blend of rosemary, garlic, and black pepper. Cumin, oregano, and curry are also popular seasonings for lamb.
You will also need a rack inside of a roasting pan, like the one below. If you do not have a pan like this, a deep casserole dish or dutch oven will also work. Cooking times may vary depending on these changes.
What size lamb roast should I buy?
This is a question I struggled with for a long time. My secret: always estimate more than what you need. I always account for about ½ pound of meat per serving. Most people don’t actually eat that much, especially if you are factoring in children.
With ½ pound per person, here’s a chart for getting the right size for the number of servings:
Servings | Weight of Roast |
---|---|
6 people | 3 pounds |
8 people | 4 pounds |
10 people | 5 pounds |
12 people | 6 pounds |
12+ people | purchase 2 roasts |
Lamb Roast Internal Cooking Temperatures
If you take nothing else away from this article, hear this: Please. Please. Please. Use an in-oven meat thermometer.
You can pick them up off of Amazon, Target, Wal-Mart, or just about any grocery store.
Internal temperature – not time – will yield the perfectly tender result that you want!
The internal temperature is all a matter of taste. Personally, I prefer lamb right at the threshold between Medium Rare and Medium. It’s still pretty pink in the center but not overly runny. The red juices, by the way, are not blood, but a protein in the meat that is released when cooked.
To reach your desired doneness and temperature, follow this chart:
Level | Internal Temp (F) | Looks Like |
---|---|---|
Rare | 120-125F | Bright red center, pinkish toward exterior |
Medium Rare | 130-135F | Pink center, slightly browned toward exterior |
Medium | 140-145F | Light pink center, outer portion is brown |
Medium Well | 150-155F | Not Pink |
Well Done | 160F and above | Uniformly brown throughout |
What is the cooking time for a leg of lamb?
Of course, the time it takes to reach the desired internal temperature is determined by the weight of the lamb roast.
Keep in mind that all ovens vary, which is why it’s so important to use an in-oven meat thermometer while cooking, so you can monitor the process.
As a general guide, refer to this chart when preparing estimates for cook time:
Weight | Rare (120-125F) | Medium-Rare (130-135F) | Medium (140-145F) | Well Done (160-165F) |
---|---|---|---|---|
1 pound | 15 minutes | 20 minutes | 25 minutes | 30 minutes |
2 pounds | 30 minutes | 40 minutes | 50 minutes | 60 minutes |
3 pounds | 45 minutes | 60 minutes | 1 hour, 15 minutes | 1 hour, 30 minutes |
4 pounds | 60 minutes | 1 hour, 20 minutes | 1 hour, 40 minutes | 2 hours |
5 pounds | 1 hour, 15 minutes | 1 hour, 40 minutes | 2 hours, 5 minutes | 2 hours, 30 minutes |
6 pounds | 1 hour, 30 minutes | 2 hours | 2 hours, 30 minutes | 3 hours |
Tips for this recipe
- After the roast is removed from the oven, it will continue cooking as it rests. The longer the meat rests, the higher the internal temperature will rise. Keep this in mind when you are calculating serving and cooking times.
- If you do not have an in-oven thermometer, use a regular meat thermometer to begin checking the internal temperature about 30 minutes before the estimated roasting time ends.
- Bringing the meat to room temperature is crucial for a well-roasted cut of meat. Otherwise, you could end up with a tough roast.
Boneless Leg of Lamb Recipe
Ingredients
- 3 cloves garlic minced
- 2 teaspoons fresh rosemary leaves coarsely chopped (1 teaspoon dry rosemary leaves)
- ¼ teaspoons black pepper
- ½ cup olive oil extra-virgin
- 2 tablespoons lemon juice fresh-squeezed
- 4 pound Boneless Leg of Lamb Roast
Instructions
Make the Herb Seasoning Rub:
- Allow the uncooked lamb to come to room temperature – about 1 hour.
- Combine the garlic, rosemary, black pepper, olive oil, and lemon juice in a small bowl. Whisk to combine, and set aside.
- Preheat oven to 450 degrees F.
Prepare the Lamb:
- Remove the lamb from the package, but keep the netting on. Pat the roast dry with paper towels, and place on a rack of a roasting pan.
- Apply the rub on all sides of the lamb roast.
- Insert an oven-proof meat thermometer into the center of the roast, making sure the tip of the probe is not exposed but inserted into the meat.
Roast the lamb:
- Place the uncovered lamb roast in a 450F degree oven for 15 minutes to create a “seared” effect and a flavorful brown crust.
- After 15 minutes, reduce the oven temperature to 325F degrees for the remaining 1 hour and 20 minutes of cook time. (uncovered; for a 4 pound roast to medium-rare)
- Continue cooking until the meat thermometer reads 120F degrees. Remove from the oven and cover with aluminum foil. Allow to rest for approximately 15-20 minutes, or until it reaches the desired internal temperature. (see chart above)
- As you are ready to carve, place the roast on a cutting board with a well to catch juices. Remove the netting with scissors.
- With a carving knife, slice the meat across the grain into desired thickness. Serve immediately.
I amde this exactly as written and it was FANTASTIC! So easy, and perfectly done.
Why must it come to room temperature? Can you explain the science behind that?
@Gin, I believe the reasoning being if it is cold it will cook unevenly and you risk the middle not coming up to temperature. It’s similar with chicken.
You could cook it from cold, but it would take longer and it might not cook fully on the inside without risking the outside overcooking.
Hope that helps!
Made this tonight and it was just right. 3 lb. boneless leg. Thanks for the cooking guide.
Just added more dried oregano and salt. I noticed you don’t have salt in the ingredients.
Use the drippings to season gravy👌
Hi Anna,Kate, I am from Scotland, lived here for many years, my mom and Nana and now me ,make lamb or leg of lamb just like your recipe. It’s a pretty common Sunday dinner over there. Anyway I learned how to fix it from watching them while growing up. Only difference I can see. We all stabbed the roast all over and inserted garlic cloves, and mom made mint sauce with malt vinegar , a little sugar and fresh peppermint. She would leave it on stove while she cooked roast to bring out flavors. I do same . I can’t imagine having lamb without mint sauce. My grown kids now, loved it too. I haven’t made one for some time ,you have inspired me . Yours looked amazingly delish. Sorry this is so long . Ps the crab cakes recipe sounds amazing too. Thanks so much. I will be following. Gina.
Gina, Thank you so much for your comment! I’m so glad this recipe inspired you to make this again. I’m so thankful I can be a part of special memories, too.
Hi Anna,Kate, I am from Scotland, lived here for many years, my mom and Nana and now me ,make lamb or leg of lamb just like your recipe. It’s a pretty common Sunday dinner over there. Anyway I learned how to fix it from watching them while growing up. Only difference I can see. We all stabbed the roast all over and inserted garlic cloves, and mom made mint sauce with malt vinegar , a little sugar and fresh peppermint. She would leave it on stove while she cooked roast to bring out flavors. I do same . I can’t imagine having lamb without mint sauce. My grown kids now, loved it too. I haven’t made one for some time ,you have inspired me . Yours looked amazingly delish. Sorry this is so long . Ps the crab cakes recipe sounds amazing too. Thanks so much. I will be following. Gina.