Getting a perfectly roasted leg of lamb is easier than you think. From perfectly trussing the roast to getting the perfect sear, I’ll show you how to roast a leg of lamb to impress dinner guests.
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Lamb is such an underappreciated meat. Here in the States, we have the famous trifecta of proteins that are most consumed: chicken, pork, and beef. Lamb is such a fun protein to cook because it’s super versatile. Perfectly cooking lamb is much easier to do than you think.
One of the essential keys to getting a perfect roast is by properly trussing. What’s trussing? Trussing is, basically, where you use butchers twine to tuck a roast together so that everything is tight and cooks evenly. When butchering a roast cut, you often have to de-bone the meat which makes the roast uneven. If you were to cook the roast without trussing, there would be unevenly cooked pieces in the roast. Trussing ensures even cooking throughout the roast. For help with trussing, here is a quick video!
Now, you can definitely feel free to marinade your lamb roast overnight but because I was pairing this roast with a mint pesto, I didn’t want to overpower the flavors of mint with anything else. A simple, but liberal seasoning with salt and pepper on lamb is just fine. Plus, since we’re roasting this to medium-rare, the roast is going to be plenty juicy!
The biggest secret of all to making a perfectly juicy roast, lamb or otherwise, is by locking in the juices with a hard sear before roasting. I mentioned this in this post but it makes a huge difference in the outcome of the lamb roast. Searing helps keep the juices locked in the roast; I especially love using a cast iron skillet to sear roasts for two reasons.
- First, it gets super hot and retains the heat really well, guaranteeing a fantastic sear.
- Second, it withstands hot temperatures well, which is super ideal with roasting in a really hot oven.
Preheating your oven to a high temperature, like 500, also helps set in the juices. I like to set my oven to 500 and then before putting the roast in the oven, dropping the temperature to 275. This lets my lamb cook at a moderate pace which ensures a super moist roast.
The roast only takes about an hour and a half before reaching 125 degrees, which is when I prefer to take out my lamb roast. This is because it will continue to cook as I let it rest and the roast will gradually get to 135, which is a perfect medium-rare.
I like to top my lamb roast with a mint pesto. With some basil and toasted almonds, it’s a perfect accompaniment to the roast. I also like pairing this roast with Italian Mashed Potato Casserole; your family will love it as well, I guarantee!
Let me know how you and your dinner guests like this roast and how it turns out!
If you are looking for other main dishes for a holiday dinner, be sure to check this post of 15+ Main Dishes for a Non-Traditional Holiday Dinner.
- 5 lb leg of lamb roast
- To taste salt and pepper
- 10 pieces of fresh rosemary
- 10 cloves of garlic
- 1.5 ounces mint
- .75 ounces basil
- ¼ cup toasted almonds
- 1/3 cup olive oil
- 1 tbsp lemon juice
- Preheat oven to 500 degrees. Liberally season lamb roast with salt and pepper. Truss with butchers twine to keep roast together tight.
- Next, create 10 slits within the roast to stuff rosemary and garlic in.
- Preheat a cast iron skillet over medium high heat with a small amount of oil in the pan. Next place trussed roast in skillet and begin to sear the lamb. Sear the first side of the lamb for about 5 minutes or until golden brown. Continue to sear all 4 sides in the pan.
- Drop the heat of the oven to 275 degrees and place roast in oven. Set timer for 1 ½ hours and check temperature. Pull at 125 for medium rare and 135 for medium and allow to rest for about 15-20 minutes before slicing into roast.
- Toast almonds in a 350 degree oven for 5-7 minutes. In a food processor, process herbs, almonds, lemon and seasonings. Gently drizzle olive oil until well incorporated. Keep in an air tight container for up to 5 days.
Nutrition InformationYield 8 Serving Size ounces
Amount Per ServingCalories 342 Saturated Fat 4g Cholesterol 114mg Sodium 113mg Carbohydrates 3g Fiber 1g Protein 38g