This Leg of Lamb Recipe is infused with rosemary and garlic, then oven roasted to perfection until tender. Easy recipe for your next Sunday dinner, Easter or holiday meal.
Also here is how to roast boneless leg of lamb.
Table of Contents
- What Is a Leg of Lamb?
- Tips for Buying Leg of Lamb
- Should I Marinate a Leg of Lamb?
- Should Leg of Lamb be Cooked Fast or Slow?
- Internal Temperature Guide for Roasted Leg of Lamb
- Ingredients You Will Need
- How to Cook Leg of Lamb Recipe
- Serving Recommendations
- How to Store and Reheat It
- More Lamb Recipes to Try
- Leg of Lamb Recipe Recipe
Many feel intimidated when it comes to lamb but I can tell you it is one of the easiest cuts of meat to cook. The secret is not to over cook it because lamb is naturally tender and flavorful. Stick with me and I will show you how to roast leg of lamb to perfection.
What Is a Leg of Lamb?
Bone-in leg of lamb comes from the hind legs of the animal. It is the large thigh part of the leg, usually weighing 5 to 7 pounds, and is more flavorful than boneless leg of lamb.
It is mostly sold without the shank attached, but you can purchase one with the shank known as “American leg” or “shank-on leg” if you want a more traditional presentation.
Tips for Buying Leg of Lamb
Here are my valuable tips for selecting the best leg of lamb roast.
- Buy from a reputable butcher: Because it is a more expensive cut of meat, I recommend buying from someone you trust. You can ask questions and the meat will likely be from local farms.
- Ask him to trim the fat: For a less gamey taste. A little bit of fat is good to insulate the meat and keep it tender but too much can have a strong flavor.
- Be sure to buy market weight lamb: This means no baby lambs or older lambs that would have a tougher meat.
- If you buy fresh or frozen leg of lamb from the grocery store: Most grocery stores have lamb leg in their meat department and it is good for this leg of lamb recipe. More likely it comes from New Zealand or Australia, which is fine to use too.
Should I Marinate a Leg of Lamb?
Roasted leg of lamb is tender and does not have to be marinated. I always season the lamb with fresh herbs and spices for the best flavor. My favorite seasonings are garlic and rosemary, for this leg of lamb recipe I added thyme and Dijon mustard for a richer taste.
I recommend making shallow diamond cuts on top before applying the rub mixture. Scoring helps tenderize the meat, increases flavor and gives the outer edge a brown crispy skin.
Should Leg of Lamb be Cooked Fast or Slow?
For rave worthy presentation and taste, leg of lamb roast should be cooked one of two ways.
I like roasting in the oven until the inside is perfectly pink and juicy with an internal temperature of 130 F. You can also roast slowly for hours until you have very tender, fall apart meat. You can use your slow cooker but oven roasting is ideal.
Internal Temperature Guide for Roasted Leg of Lamb
The amount of time it takes to roast leg of lamb depends on your desired doneness. I’ve included a simple time chart as a guideline but there are a few factors to keep in mind.
Lamb will keep cooking after you take it out of the oven and the internal temperature will rise as it rests. Your lamb leg may roast slower or faster depending on your oven.
|Desired lamb doneness||Internal Temperature||Time|
|Medium rare||130F – 135F||20 minutes/lb|
|Medium well||140F – 145F||30 minutes/lb|
|Well done||150F – 155F||35 minutes/lb|
Ingredients You Will Need
To make leg of lamb recipe you need 7 day to day simple ingredients.
- Bone-in leg of lamb: Mine was about 5 pounds. Be sure to bring it to room temperature before roasting for even cooking and an accurate temperature reading.
- Olive oil: For making the spread. Extra-virgin olive oil goes well with lamb but you can also use avocado oil.
- Dijon mustard: One of my favorite condiments for lamb and adds a mild spicy kick to the dish.
- Garlic: Use freshly minced garlic cloves for best results.
- Fresh herbs: Fresh rosemary and fresh thyme add an aromatic savory flavor and is the perfect combination for lamb.
- Salt and pepper: To season and taste.
If you would like to add baby potatoes, toss them with some olive oil, salt and pepper and spread around the lamb roast 45 minutes before expected finish time. Just do it with lamb out of the oven so you don’t let all the heat escape with oven door open.
How to Cook Leg of Lamb Recipe
Here is a step-by-step photo overview on how to cook a perfect lamb roast. There is very little prep time needed.
- Prep: Start by preheating your oven to 350 F and place a rack in your roasting pan.
- Score lamb: Use paper towel to pat dry leg of lamb then make shallow cuts on top. Place on your prepared baking rack.
- Combine herbs and spices: Add olive oil, Dijon mustard, garlic, rosemary, thyme, salt and pepper to a small bowl and mix.
- Season lamb: Rub the sauce over the leg. You’ll want most of the mixture to be on top, then cover the sides and a bit on the bottom.
- Roast uncovered: Roast leg of lamb in the oven until your preferred doneness. Refer to the time chart and remember to check the internal temperature often using an instant-read thermometer. Broiling at the end is optional for a golden-brown crust.
- Rest and carve: Remove roast from the oven and rest for 15 minutes uncovered to allow juices to settle. Use a sharp knife and slice. I find it easiest to start at the meaty part and cut perpendicular to the bone.
All ovens vary, so check on your lamb after about 1 hour 15 minutes. Also because it is a such large piece of meat, it is normal for different parts of it be cooked differently. Use thermometer and check the meatiest parts, away from the bone. Meat closer to the bone is more rare.
I love serving this leg of lamb recipe alongside our favorite holiday side dishes like creamy mashed potatoes, a fresh salad, and seasonal vegetables.
If you have any leftovers, cold lamb makes a delicious sandwich or salad topper!
How to Store and Reheat It
Store: Store sliced lamb roast in an airtight container and keep in the refrigerator for up to 5 days.
Reheat in the oven at 350 F. Place it in a covered baking dish to avoid over drying.
Freeze: Cut sliced lamb into bite size pieces, store in an airtight container and keep in freezer for up to 3 months. Thaw in refrigerator overnight before serving cold or reheating.
Leg of lamb is a large piece of meat. So it is normal for some part be rare and some parts of it be well done.
The total time depends on preferred doneness. Whether it be rare, medium-rare, or well done, refer to the above time chart for temperatures and times. Remember they are guidelines as ovens vary, meat varies etc.
A quality meat thermometer is a must have. Check the internal temperature often to prevent undercooked or over cooked roast.
If you find out it is undercooked, return to oven and keep cooking. Check often with internal meat thermometer.
More Lamb Recipes to Try
- Boneless leg of lamb recipe
- Lamb shanks recipe
- Lamb stew recipe
- Pan fried lamb chops
- Air fryer lamb chops
Leg of Lamb Recipe
- Preheat oven to 350 degrees F and fit roasting pan with a rack. Set aside.
- In a small bowl, combine olive oil, Dijon mustard, garlic, rosemary, thyme, salt and pepper. Mix well with a spoon.
- Pat dry leg of lamb with paper towels and make shallow cuts on top in a diamond pattern. Place on previously prepared baking rack and rub mixture mostly on top and covering the sides and bottom a bit.
- Bake leg of lamb uncovered according below timechart until desired doneness. Remember meat will keep "cooking" as it rests.°Medium Rare: 130 – 135 degrees F internal temperature – about 20 minutes/lb.°Medium Well: 140 – 145 F internal temperature – about 25 minutes/lb.°Well-Done: 150 – 155 F internal temperature – about 30 minutes/lb.
- My best advice for 5 lbs leg of lamb is to check internal temperature after 1 hour and go from there. For 2-3 lbs leg of lamb, check after 45 minutes. It all comes down to checking often after a certain period of time towards the end. You can also broil it for a bit at the end.
- Remove lamb roast from the oven and let rest uncovered for 15 minutes.
- Using a sharp knife, slice leg of lamb perpendicular to the bone starting with the meaty part most accessible to you. No hard rules.
- Serve roasted leg of lamb warm at a celebration table or use cold leftovers in sandwiches or salads.
- Store: Refrigerate leftover sliced roast 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.
- Reheat: To avoid over drying, reheat at 350 F in the oven while covered in a baking dish.
- If you would like to add baby potatoes, toss them with some olive oil, salt and pepper and spread around the lamb roast 45 minutes before expected finish time. Just do it with lamb out of the oven so you don’t let all the heat escape with oven door open.