Name: Lemon-Garlic Semi-Boneless Leg of Lamb
Prep time: 10 min
Cook time: 120 min
Total time: 130 min
Ingredients: 1 6-pound semi-boneless leg of lamb; 1 tablespoon minced garlic; Coarse or kosher salt and freshly ground pepper (to taste); Finely grated zest from 2 lemons

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Boneless Leg of Lamb

There are few large pieces of meat that my family loves more, and few that make more of a statement for company. This cut of meat may seem intimidating, but really it’s just like any other roast – the oven does most of the work, and all you have to do is make sure not to overcook it – which is where an instant-read meat thermometer comes into play.

Roasting a leg of lamb is a great reason to throw a dinner party, and if you see leg of lamb on sale at the market, that’s a fine excuse to invite the masses. I confess to being a big shop-the-sales supermarket shopper. It helps me focus, it keeps things fresh in our house, it gives me recipe development inspiration, it keeps boredom at bay, it keep me on my toes cooking wise. Once I have a main ingredient, I’m on my way. (oh, yes—and it saves some money).

Look at that crust, wouldja? That’s the result of giving the roast a blast of high heat at the beginning of the cooking time. This lemon garlic leg of lamb is a traditional and timeless combo of flavors. And just two ingredients, plus the lamb! (Ok, and salt and pepper.)

There are few large pieces of meat that my family loves more than a leg of lamb, and classic seasonings turn this favorite cut of lamb into a lush and celebratory dinner.
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What Size Leg of Lamb Serves How Many?

It’s hard to know just by looking at it, isn’t it? And bone in or bone out factors into play, since the bone is part of the overall weight of the roast. This recipe with a 6 pound semi-boneless leg of lamb will generously feed 12 to 16 people. You can plan on about 1/3 to 1/2 pound per person (1/2 pound allows for seconds, with leftovers, which are everything when you are making leg of lamb).

Therefore:

A 4 pound semi-boneless leg of lamb will serve 8 people
A 5 pound semi-boneless leg of lamb will serve 10 people
A 6 pound semi-boneless leg of lamb will serve 12 people
A 7 pound semi-boneless leg of lamb will serve 14 people

And with the leftovers you might think about Lamb Crostini with Spiced Crème Fraiche and Herbs or Cheesy Mashed Potato Topped Shepherd’s Pie – two excellent reason to make a larger than needed leg of lamb.

Cooking Leg of Lamb Perfectly

There are a few ways to look leg of lamb—one is low and slow, another is to start with the oven high for a brief chunk of time, and then lower it for the remainder of the cooking time.

Finally you can cook it fast with all high heat, but you really want to monitor the cooking time very carefully as the temperature rises quickly at the end, and you can go from medium rare to medium well in a matter of minutes.

Leg of lamb cooking time is something you want to be pretty careful about, since most people love pink slices of lamb, and aren’t as excited by well done lamb.

Cooking Times for a Semi-Boneless Leg of Lamb

The cooking times for boneless (rolled) leg of lamb is actually longer than for bone-in leg of lamb, because the bone acts like a heat conductor, according to the American Lamb Board. A semi-boneless leg of lamb is, as you would expect, somewhere in the middle.

At 325 degrees F, a semi-boneless leg of lamb will take approximately:

18 to 25 minutes per pound for rare (130 degrees F) or medium rare (135 degrees F)
25 to 30 minutes per pound for medium (145 degrees F)
30 to 35 minutes for medium well (150 degrees F) or well done (160 degrees F)

But always err on the side of checking at the shortest end of the suggested cooking time, so you can avoid overcooked meat.

Cooking Lamb Starting with High Heat

This 6-pound semi-boneless leg of lamb cooks using the second method – a high temperature to start, then low and slow. You start it at 425 F for 20 minutes, then reduce the oven temperature to 350 F and continue to cook it for about another 1 hour 30 minutes to 1 hour 45 minutes, until a meat thermometer inserted into the center of the roast registers 135 F. That’s the temperature for medium rare. Let it go to 145 F if you prefer medium-cooked lamb.

Remove from the oven and let it sit for 20 minutes to collect its juices and finish cooking before carving and serving. The temperature will rise slightly while it is sitting, but don’t worry – that’s the plan, that is what you are going for to get those tender rosy slices, and not lose all the beautiful juice to the cutting board when you slice it.

Because in this recipe the lamb starts at a higher temperature to help it form a nice outer crust, the remaining cooking time at the lower temperature is reduced slightly.

You can make this recipe, following the steps below, with a boneless leg of lamb but it may take a bit longer than the time suggested suggested for the semi-boneless cut. A bone-in leg of lamb may cook in about the same time, or even slightly faster.

The lamb can also be cooked at the higher temperature all the way through, which I did once (by accident, but it turned out ok). For a 6-pound semi-boneless leg of lamb, cook it at 425 degrees F for about 1 hour and 20 minutes, and again, rely on that meat thermometer.

What to Serve with Leg of Lamb:

It pairs beautifully with Red Onion and Mint Orzo and Roasted Cauliflower with Chimichurri Sauce. Or try Lebanese Couscous with Sautéed Kale and Lemon Dressing, Creamed Kale with Parmesan, or Orange and Herb Orzo.

Other Leg of Lamb Recipes:

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