Learn how to roast perfect Roasted Boneless Leg of Lamb Recipe every time! Herb crusted and garlic stuffed, this is an easy lamb roast anyone can make!
We also have this bone-in leg of lamb recipe.
Why You’ll Love This Recipe
My favorite way to celebrate anything is with this roasted boneless leg of lamb because it’s so easy to do but looks grande on the table!
I have been making this lamb roast recipe for Easter dinner, Holidays or whenever I need to leave a lasting impression for the past 20 years. Works every time!
- Easy recipe: Lamb is expensive, so I understand your fear of “screwing it up”. You will not thanks to my foolproof roasting method!
- Tender juicy meat: Thanks to the precise cooking times for your preferred level of doneness.
- For garlic all lovers: This boneless leg of lamb roast is stuffed with over 30 slivers of fresh garlic.
- Recipe with a video: If you are more of a visual learner, there is a video.
Reader’s Review
I’ve used this recipe multiple times for Christmas dinner and my husband always raves over the lamb when he’s normally not a huge fan of it! Using the fat droppings for roasted potatoes was also a wonderful tip! Thank you for this recipe.
Janice Luong
Ingredients for Roasted Boneless Leg of Lamb
You will need only 6 simple ingredients. General rule of thumb is to plan about 1/2 pound of roasted lamb per person.
- Boneless leg of lamb: It is a leg of lamb where bone has been removed and meat rolled, tied or netted into a shape of oval roast. You can find it in many grocery stores fresh or frozen, or in a butcher shop.
- Garlic: Fresh garlic cloves make all the difference. I don’t recommend to use garlic powder.
- Dried rosemary: Dried rosemary is more convenient. However, you can use fresh rosemary if you wish and it will yield even more flavor.
- Olive oil: Extra virgin olive oil goes well with lamb naturally. But you can also use avocado oil or grapeseed oil.
- Salt and black pepper: To season and taste.
How to Roast a Boneless Leg of Lamb
- Prep: Preheat oven to 425 degrees F while you are preparing the roast. Cut garlic into thin slivers.
- Make slits in the roast: In a medium roasting pan or Dutch oven (no need for a wire rack but you can use one), place boneless lamb roast and make about 20-30 inserts with a paring knife.
- Stuff with garlic: Stick garlic slice into each opening until you run out of garlic.
- Season with spices on both sides: Rub the roast with oil all around. Then sprinkle one side with half of rosemary, salt and pepper. Turn around and repeat on another side.
Fat Tip
Fat side up or down? Like with any roast, the best practice is to cook meat with fat side up, so it keeps it moist and juices locked in inside. It acts like a blanket.
Bake lamb roast uncovered according the schedule below until desired doneness when checked with a quality meat thermometer.
Meat will keep “cooking” as it rests. Please keep in mind internal temperature will rise while meat is resting after baking in the oven.
- Let meat rest: Remove lamb roast from the oven and let rest uncovered for 15 minutes. Do not skip!
- Remove casing: Transfer lamb roast on a cutting board. Using a sharp carving knife, remove the casing. I highly recommend to sharpen the knife before slicing, helps a lot not to destroy the roast.
- Carving roast: Slice into 1/4-inch slices against the grain. Thin slices of lamb taste better than thick slices.
How Long to Cook Boneless Leg of Lamb?
All ovens vary due to age, electric vs. gas etc. Not to mention convection oven cooks food faster. So check on your boneless leg of lamb roast earlier than later!
My best advice is for 4-5 pounds roast to check internal temperature after 1 hour and go from there. For 2-3 pounds roast, check after 45 minutes. It all comes down to checking often after a certain period of time.
| Desired lamb doneness | Internal Temperature | Time |
|---|---|---|
| Medium rare | 130F – 135F | 16 minutes/lb |
| Medium well | 140F – 145F | 18 minutes/lb |
| Well done | 150F – 155F | 20 minutes/lb |
Tips for Best Results
- Plan ahead: Just make sure you understand your dinner will be on the table in 2 hours if you roast lamb. I speak from my own experience.
- Don’t remove the casing before cooking: Under any circumstances keep netting or rope on. It is what is holding pieces of meat together. If you remove it, meat will fall apart.
- Bake roast uncovered: You need meat to brown on the outside, not steam. If you cover it with a lid or aluminum foil, roast will steam instead of roasting.
- Adjust for your oven: All ovens vary, I can’t stress this enough! If your oven runs hotter or takes longer to cook, adjust cook time accordingly to avoid overcooked or undercooked lamb. Rule of thumb is to start checking with instant-read thermometer 1/2 hour before end of cook time as per recipe.
- If you use a convection oven method: It cooks food faster than regular oven. I recommend to reduce the temperature by 25 degrees F.
To Roast Potatoes in Fat Drippings
This step is optional. Lamb is extremely fatty meat, you will see a lot of fat and pan drippings at the bottom of roasting pan. Take advantage of it to make lamb and potatoes (and other veggies), so good!
- Remove some fat and drippings: Scoop out 1 cup of drippings as it is just too much and roasted vegetables will come out too greasy.
- Add veggies and seasonings: I added about 2 pounds baby potatoes, 2 carrots, 1/2 tablespoon garlic powder, 3/4 tsp salt and ground black pepper to taste. Then stir to coat.
- Bake lamb: At 450 degrees F for about 35 minutes or until fork tender. You can prep the veggies and seasonings while lamb is cooking, so after just pop them in without even turning off the oven.
Serving Ideas
Serve sliced roasted boneless leg of lamb on its own, or drizzled with freshly squeezed lemon juice or fresh mint jelly. We usually have lemon on hand at all times, so it rounds up meat flavors nicely.
- Sauces: Aside mint jelly and traditional gravy, chimichurri sauce adds bright tangy flavor to roasted lamb.
- Potatoes: Lamb roast would be delicious with mashed potatoes, sweet potato mash, crispy Parmesan potatoes or this genius cauliflower mashed potatoes.
- Salads: Look for salads that are bright and colorful like spinach avocado salad, tomato cucumber feta salad or this spinach salad recipe.
- Vegetables: Garlic green beans and baked asparagus are just classics.
How to Store
Store: Refrigerate lamb leftovers whole as a roast or sliced in an airtight container for up to 5 days. It tastes so good cold!
Freeze: Freeze leftover lamb sliced or cut into bite sized pieces in an airtight container for up to 3 months. Thaw in the fridge and then use as a protein in a salad for lunch or sandwich on-the-go.
FAQs
Yes, you can stuff and season roast, cover and refrigerate for 24 hours. Then let it come to room temperature and roast as per recipe.
This leg of lamb recipe should be cooked uncovered.
Yes, you can cook 2 lamb roasts at same time if both of them fit into your Dutch oven or roasting pan in a single layer. Also you can use 2 separate Dutch ovens at same time as long as they fit on the same bottom shelf of your oven.
More Lamb Recipes to Try
- Braised lamb shanks
- Lamb stew
- Pan seared lamb chops
- Air fryer lamb chops
- Lamb loin chops
- Grilled lamb kofta kebabs
More Roast Recipes to Try
Roasted Boneless Leg of Lamb
Equipment
Video
Ingredients
Boneless Leg of Lamb Roast
- 4-5 pounds boneless leg of lamb
- 5-7 large garlic cloves, cut into slivers
- 2 tablespoons olive oil, extra virgin
- 2 tablespoons rosemary, dried
- 1 1/4 teaspoons salt
- Ground black pepper, to taste
Roasted Potatoes After (Optional)
- 2 pounds potatoes, cubed
- 2 large carrots, sliced
- 1/2 tablespoon garlic powder
- 3/4 teaspoon salt
- Ground black pepper
Instructions
- Preheat oven to 425 degrees F.
- In a medium roasting pan or Dutch oven, place boneless leg of lamb roast and make 20-30 inserts with a paring knife. Stick garlic slice into each opening until you run out of garlic.
- Rub roast with oil all around. Then sprinkle one side with half of rosemary, salt and pepper. Turn around and repeat on another side.
- Bake uncovered according until desired doneness. Remember meat will keep "cooking" as it rests.°Medium Rare: 130 – 135 degrees F internal temperature – about 16 minutes/lb.°Medium Well: 140 – 145 F internal temperature – about 18 minutes/lb.°Well-Done: 150 – 155 F internal temperature – about 20 minutes/lb.
- My best advice for 4-5 lbs roast is to check internal temperature after 1 hour and go from there. For 2-3 lbs roast, check after 45 minutes. It all comes down to checking often after a certain period of time towards the end.
- Remove lamb roast from the oven and let rest uncovered for 15 minutes.
- Using a sharp knife, remove the casing and discard it.
- Slice lamb into 1/4 inch slices against the grain. Serve warm at a celebration table or use cold leftovers in sandwiches or salads.
Roast Potatoes in Fat Drippings (Optional)
- Scoop out 1 cup of fat and drippings from the pan and leave in the rest.
- Add potatoes, carrots, garlic powder, salt and pepper and stir well.
- Bake at 450 degrees F for about 35 minutes or until fork tender. You can prep the veggies and seasonings while lamb is cooking, so after just pop them in without even turning off the oven.
Notes
- Make ahead: To save time during a busy day of cooking of a holiday, you can stuff and season roast, cover and refrigerate for 24 hours. Then let it come to room temperature and roast as per recipe.
- Store: Refrigerate roast whole or sliced in an airtight container for up to 5 days. It tastes so good cold.
- Freeze: Freeze leftovers sliced or cut into bite sized pieces in an airtight container for up to 3 months. Thaw in refrigerator.
- Don’t remove the casing before cooking: Under any circumstances keep netting or rope on. It is what is holding pieces of meat together. If you remove it, meat will fall apart.
- Adjust for your oven: All ovens vary. Rule of thumb is to start checking with internal meat thermometer 1/2 hour before end of cook time as per recipe.
- Meat will keep “cooking” as it rests: Please keep in mind internal temperature will rise while meat is resting after baking in the oven.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
I made this recipe for my family for Christmas dinner this year – can’t remember the last time I cooked a leg of lamb, so I was a little bit nervous. It came out perfectly cooked at 135 degrees F using the cooking times provided, and it was so delicious I couldn’t believe it. And the potatoes cooked in a thin layer of lamb fat were heavenly. Thanks for helping my Christmas be extra special this year!! It will be my go-to Christmas dinner now.
So glad you enjoyed it Sharon! Happy holidays!
It exceeded my expectations. I discovered that the thermometer I was using was registering too low of a temperature. I took measurements as per the receipt and used an alternative thermometer to discover this. The results were fantastic. Best lamb roast I’ve ever made. I’m curious about why he had the plumber over while cooking. I used to be a plumber in my second career and the cooks couldn’t afford to keep me around.
Glad you enjoyed it!
Best lamb leg I’ve ever eaten, I can’t believe that I cooked it at home following this recipe as opposed to at a fancy restaurant! I got the same bottle of olive oil as on the photo (Terra Delyssa from Whole Goods)
Yeah! So happy to hear of the lamb roast success! Happy Holidays!
My standard go-to, but I needed to confirm the cooking time. I agree with Olena. I was raised in France and just plain old fresh ingredients is the way to health. With that in place, you won’t need to “diet”
Thanks for the kind words, glad to hear this is your go-to!
Hi, You say to let lamb sit for 15 min after taking out of the oven but the potatoes/veggies will take 45 min after that. Do you reheat the lamb after the potatoes and veggies are done?
I don’t reheat the lamb. I keep it covered with a few layers of aluminum foil in the meanwhile or you can keep it warm in a warming drawer if you have one, or place in a microwave but don’t turn on.
Thank you! One mote question: how often do i keep checking the roast after the initial cook time (in my case, 45 min for a 2.5 lb roast)?
Approximately every 5 minutes or so.
Thank you for easy to understand instructions. Love leg of lamb!
So glad you enjoyed it!
Absolutely fantastic recipe. My first attempt at a leg of lamb, and it was a home run.
So happy to hear it was a success Edwin!
Going to try this recipe, just wondering about making a sauce with leftover juice, any thoughts? Thanks
Right… Leftover juice has a lot, a lot of fat. I would keep only 1 cup, add 1 cup any broth and follow this turkey gravy recipe. Of course, double other ingredients too.
I don’t cook red meat much at all, so I was nervous about how to roast a boneless leg of lamb. Thank you for making it so straightforward and also it was delicious! One thing – your recipe says to preheat/roast at 425 degrees, but then for roasting the potatoes afterwards, says to do it “at the same 450 degrees” – suggest you fix that. 🙂
Thanks for letting us know, we will get that fixed! And so happy to hear it went so well cooking wise!
This still has not been fixed. So, is it 425 or 450. I’m cooking now ar 450.
It’s 450. I fixed it now, sorry about that. You can cook it at either T as these veggies aren’t delicate so either T will work. Enjoy!:)
Where can I see the video for this delicious recipe?
In bottom left corner of your screen. If you are running an ad blocker, you will not see it though. Hope this helps.