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.
Yum! My house smells so good and this is the first time I’ve made this. Thank you for sharing your family favorite!
So happy to hear that you enjoyed this Debbie!
Thank you I’m trying it right now. I have the oven set at 360 but you’re recommending a much higher temperature so maybe I should turn the oven up, I don’t want to burn but I don’t want it rare either. I am looking for my meat thermometer oh dear!
How did the leg of lamb turn out Kathy? Yes, I do recommend a higher temperature of 425F as I find it yields juicy meat inside with a nice browned outside. You just need to check the meat regularly with an internal meat thermometer!
Perfect…. Thank you for all the instructions…. I know it is simple but some people don”t know how to do it… All these instructions and videos have made me a really good cook..
I’m so happy to read this! Thanks for your positive feedback, Patricia!
How long do you keep a boned leg of lamb covered whilst roasting?
I am not sure. Haven’t baked it in a while.
I love all you share with such care. You make every recipe so easy to follow. Thank you for all you share. My 4 1/2 boneless lamb roast came out wonderfully. I made it today for our 2020 New Year’s dinner. Every one ate until totally happy. My whole family asked for the recipe. Absolutely love your recipe. Thank you.
T.
Awe, you are so welcome, Tanya! So happy to hear you are enjoying my recipes! Thanks so much for sharing my recipe with family and friends!
This is a good recipe to save since I didn’t have to buy ingredients I didn’t have on hand. The cooking time was perfect and we all enjoyed the meal. There was more slivered garlic left after I filled the inserts, so I made a few more slashes in the lamb and added more garlic.
The cooking time was perfect and the lamb was pink in the center after 90 minutes at 425 degrees. Next time I’ll remember to roast some veggies along with the lamb.
So happy to hear, Elaine. Merry Christmas!
The timing and internal heat suggestions were so helpful! I’ve never made lamb before and this recipe made it very easy and turned out great! Thank you!
You are very welcome, Laura!:) Happy Holidays!
Wonderful way to cook lamb: great taste and so easy. Thank you.
That is so amazing to hear! Glad you enjoyed my recipe, Janet.
I plan on trying your recipe on Christmas. I hope to use the rotisserie on my power air fryer (if the lamb is no to big). I know the cooking times and oven temperature will be different
Good luck! Please let me know how it turns out. I am yet to try an air fryer. 🙂
What kind of roasting pan do you use? Stainless steel? Aluminum? Non-stick?
Also, do you use a rack in the pan so the fat drips off?
Just this 6 quart Lodge dutch oven. No rack.
Thank you!!
Bought a 5 pound Costco boneless roast and followed the directions exactly. Surprisingly, came out a little tough. I think perhaps my husband cut the slices a little too thick, so that may be why. I will try making it again for Easter.
Hm… Could be many reasons. Here is what I found https://www.chowhound.com/post/tough-lamb-973363?page=2 I know sometimes same Costco lamb cut is more tough than others can be. I wonder if it is mostly specific batch fault. Hopefully next time. 🙂