Roasted Boneless Leg of Lamb

This easy roasted boneless leg of lamb recipe is quick to prepare. The lamb leg is flavored with a marinade of olive oil, garlic, lemon juice and fresh rosemary leaves, before being roasted in the oven.

 

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Full Recipe Ingredients/Instructions are available in the 
recipe card at the bottom of the post. 
You can find important tips/tricks in the
blog post.

Lamb is a great-tasting meat, with a robust, almost gamy flavor. For this reason, it and can take on strong flavors like the garlic, lemon, and rosemary I’ve used in the marinade. I like to marinate the meat before roasting as it really intensifies the flavor of the meat and also stops the joint from drying out while roasting.

I have marinated this leg of lamb for as little as 30 minutes, but a 24-hour marination works well with this cut. The longer the marinade, the more intense the flavor.

Roasted leg of lamb is a great meat to serve, as a 5 pound boneless leg of lamb will easily serve eight people. This makes it a great alternative to more traditional roasts like turkey, chicken or beef during Thanksgiving, Christmas, or other holiday gatherings.

If you love to cook with lamb, be sure to try my Air Fryer Lamb Chops or my Moroccan Soup!

Ingredients

Here is what you will need for this recipe:

• Marinade– Olive oil, Garlic, Fresh rosemary leaves, Fresh Lemon juice, Kosher salt, and black pepper.
• Boneless leg of lamb (netted or wrapped in twine – get your butcher to do this)

How to roast boneless leg of lamb

Add olive oil, garlic cloves, rosemary leaves, lemon juice, kosher salt, and black pepper to a mini food processor and process until smooth. 

Pat the lamb dry and rub the mixture over the lamb, getting the mixture into the netting. Cover and let the lamb marinate in the refrigerator for up to 24 hours.

When ready to roast, preheat the oven to 450 degrees Fahrenheit. Optional step: In a large cast iron skillet, add onion, garlic cloves, rosemary, and oil. Place the cast iron skillet in the oven for 10 minutes to get it nice and hot. When ready to roast the lamb, place the lamb on top of the hot skillet. This will give you delicious melted onions and garlic when done. You could also skip this step and roast your lamb in a roasting pan.

Place the lamb in the cast iron skillet on top of the onions, fat cap facing up. Roast the lamb at 450 degrees Fahrenheit for 15 minutes. 

ProTip – use a leave-in probe themomter when roasting this lamb. It’ll monitor the temperature of your meat while it cooks, helping to ensure you remove the roast at the right temperature.

After 15 minutes, reduce the oven temperature to 325 degrees and continue roasting until the internal temperature of the lamb reaches your desired temperature (about 1 hour and 20 minutes for medium). 

Remove the lamb from the oven and allow it to sit for 10-15 minutes. Then remove the netting, slice, and serve.

Boneless leg of lamb cooking time

When cooking lamb, the internal temperature varies depending on how you like your lamb cooked. The internal temperatures are as follows:

• Rare: 115-120F
• Medium rare: 125F
• Medium: 130F
• Medium-well: 145F
• Well-done: 150F

Expert Tips

These tips will help you make the best-roasted lamb leg you’ve ever tasted. 

• If time allows, you can marinate the lamb for more flavor. Marinate in the fridge for up to 24 hours as a longer marinade time will improve the flavor.
• A probe thermometer is the easiest method of checking the internal cooking temperature of lamb, or any other meat, to ensure it is done.
• Once the lamb leg has finished cooking, remove it from the oven and set it aside to rest for 10-15 minutes before slicing and serving. This will allow the juices to be absorbed back into the lamb and results in moist and tender slices of meat.

Variations for this Boneless Leg of Lamb recipe

I make a simple marinade for the lamb using garlic, lemon, and fresh rosemary along with some salt and pepper. However, lamb is a great meat to add flavor to so here are some other suggestions if you want to mix things up.

• Ground spices: anise, cardamon, cinnamon, cumin, nutmeg
• Herbs: dill, garlic, mint, parsley, rosemary, thyme.
• Citrus: as well as the lemon juice, add some finely shredded lemon zest.

How to serve my roasted leg of lamb  

When I’m served a roasted joint of meat, like this boneless leg of lamb, I like to serve a potato side and at least 2 other vegetable sides.

When it comes to great-tasting potato sides, you can’t beat my Creamy Instant Pot Mashed Potatoes, Garlic Mashed Potatoes, or my Cheesy Scalloped Potatoes. For a great alternative to regular potatoes, try my Mashed Sweet Potatoes or my Southern Candied Sweet Potatoes.

For vegetable sides try my Sweet & Spicy Air Fryer Brussels Sprouts, Instant Pot Buttered Cabbage, Southern Green Beans, Air Fryer Carrots or Marinated Air Fryer Vegetables.

How to store roasted leg of lamb

To refrigerate: Keep any leftover lamb in an airtight container in the fridge for 3-4 days.

To freeze: Once cooked and cooled, slice the leg of lamb and place it into an airtight container and store in the freezer for up to 3 months. Defrost overnight in the refrigerator when you are ready to enjoy.

FAQs:

If you have tried this Roasted Boneless Leg of Lamb recipe, or any other recipe on my blog, then please rate it and let me know how it turned out in the comments below!