The Food Lab's Complete Guide To Buying, Storing, and Cooking a Leg of Lamb
In the U.S., there are a few symbols that automatically come to mind around Easter time: Chocolate eggs laid by rabbits, which represent the free chocolate that Jesus passed out after the Sermon on the Mount; lilies, which represent the flowers Moses always wore in his hair; and lamb, because it's delicious.
At least, I think it's delicious, and if you're to believe the food media, it's destined to be one of the hot menu items of 2011, with chefs toying around with lamb bacon, lamb ribs, all-lamb tasting menus, and the like. But statistics tell us a different story. Here's the average U.S. per capita consumption of a few different types of meat:
That's right. We eat over 100 pounds of chicken per year each, but when it comes to lamb, we eat only 0.8 pounds per year, and the amount is getting smaller every year—back in the 1970s, it was at a larger, but still woefully tiny, three pounds per year. Not only that, but the vast majority of Americans don't eat a single bite of lamb all year. Most of this per capita consumption comes from minority communities—Greeks, Muslims, Indians—who eat a ton of it, bringing up the entire average.
Even more dire is the fact that lamb is what economists call an "inferior product," which means that its demand is inversely proportional to average consumer income. When people have money to spend, they'd rather spend it on beef and chicken breasts. A 2001 study from Kennesaw State University in Georgia found that for every 1% increase in consumer income, there was a corresponding 0.54% decrease in lamb consumption.
It's an odd dichotomy, because while in many communities, lamb is seen as the "cheap" meat—the meat to buy when you can't afford beef—in high-end food and fancy supermarket circles, it's often far more expensive—and desirable—than beef.
I'm with the latter camp. I can think of precious few situations when I'd rather have a steak than a fatty, musky lamb chop. Or when I'd rather have a pot roast than a rich, slightly funky braised lamb shank. And when it comes to holiday roasts, the Prime Rib may be the king of the table, but the roasted leg of lamb is his wilder, funner cousin.
Lamb marketers have long known of the trouble with selling their product to consumers reluctant to leave the safety of their beloved chicken and beef and have responded by carefully breeding and raising lamb that is more suitable for the American palate as well as selling it in forms that are increasingly easier and easier to cook. Indeed, if you haven't at least attempted to cook lamb for yourself at home yet, you've really no excuse.
And what better time to start than now?
We roasted our way through a half dozen lamb legs and chatted with Mark Pastore at Pat LaFrieda Meats to put together this complete guide to buying, storing, and cooking lamb leg.
Domestic vs. Imports
I see lamb from Australia, New Zealand, and the U.S. at the butcher. What are the differences between these options, and is one better than another?
There are major differences both in terms of flavor, size, and price when it comes to American lamb vs. lamb from Down Under.
- New Zealand/Australian Lamb are quite small in size, with whole legs coming in at around 5 to 6 pounds. According to Mark Pastore, it's a matter of both genetics and feed. Lambs from Down Under are smaller to begin with, and they spend their entire time grazing on grass, giving them a more intensely gamy flavor that some people can find off-putting. They also tend to be lower in fat, making them a bit harder to cook properly—legs in particular have a tendency to dry out. That said, if you're cooking for a smaller party—6 to 8 people or so—and you value gamy flavor over tenderness or richness, NZ or Aussie lamb is a good choice.
- American Lamb, on the other hand, are larger, fattier, and sweeter in flavor. Most American lamb are fed on grass most of their lives which gets supplemented with grain for the last 30 days before slaughter. The lamb at LaFrieda comes from Mennonite farms in Colorado that finish their lamb on a combination of grain, honey, alfalfa, wheat, and flaked corn. The results mean a much larger layer of protective fat around the legs, as well as better marbling. The lamb bastes itself as it cooks, helping it to maintain a moister, more tender texture. Because of the grain supplements, American lamb tends to also have a less funky, richer favor. A single leg of American lamb can weigh up to 15 pounds or so, with enough meat to feed over a dozen.
But I've read that grass-fed meat is always better—better tasting, better for the animal—is there any truth in this?
It depends on your point of view. Some people do prefer the gamier taste of 100% grass-fed lamb, while others prefer the richer flavor and juicier meat in grain-finished lamb. As far as the health of the animal goes, while it's true that an animal that lives solely on grain would eventually develop health problems (much like a human who exists solely on hamburgers), grain finishing only takes place for the last 30 days of a lamb's life, after which it's going to be slaughtered anyway. This time period is not nearly long enough for the animal to develop any health problems that would cause it to suffer in any way.
In fact, given the choice between grass and grain, sheep (and cows, for that matter), choose grain every single time. Finishing sheep on grain is as simple as providing grain to feed on in their fields. They could still eat grass if they wanted to, but they choose not to. As Mark Pastore from Pat LaFrieda Meats puts it, "If we were them, it'd be like giving us a steak and a bowl of salad. Most of us are gonna pick the steak."
And what about the price differences?
Unfortunately, American lamb tends to be more expensive than the imports, despite their long journey across the globe. It's a matter of scale. Australia and New Zealand's lamb output is several times greater than that of the U.S. If you value tenderness and juiciness, the extra cost is probably worth it.
I'm confused by all of the butchering options I have when buying a lamb leg. What should I be looking for?
Bone-in leg of lamb like the one above comes in two forms: shank end, and sirloin end (occasionally, you'll find a massive one for sale with both the shank and the sirloin still attached). The shank end lamb legs start at just above the lamb's ankle and go to midway through the calf bone, while the sirloin-end legs start at the hip and stop at around the knee.
I prefer the sirloin end because the meat is fattier, more tender, and the cut is more evenly shaped, making it easier to cook evenly. On the other hand, the shank end tends to have slightly more flavorful meat. Its tapering shape is desirable for some cooks, who like being able to offer both medium-rare meat from the thick upper part and well-done meat from the thin lower part all off of the same roast.
Because the cone acts as an insulator, bone-in lamb leg cooks faster than boned lamb leg, giving you more leeway in terms of hitting the exact doneness you want.
Boneless leg of lamb often comes sold in netting like this in order to help keep its shape during cooking. It offers several advantages to bone-in lamb. First of all, it's lighter, making the arduous task of lifting it in and out of the oven much easier on the back. It's also easier to calculate how much you need to feed your party. Finally—and this is probably the greatest advantage of all—it's far easier to carve—just cut straight through it into neat, even slices.
Of course, because of the lack of bone, it's slightly harder to cook it to the exact temperature you want (not really a problem if you've got a decent digital read thermometer—and you do have one of those, right?).
Butterflied leg of lamb is a boneless leg of lamb that has been split open and rolled out. This is how I prefer to purchase my lamb; it affords me opportunities to season it both inside and out. Often this just means a quick rub with salt and pepper before rolling it up and tying it, but often it can mean more elaborate rubs or herb mixtures. If you choose to go with a butterflied leg, you'll need to know how to tie it up before roasting.
I have a crazy friend who says it's wrong to eat meat. Is he crazy?
No, just ignorant. You see, your friend never heard of the food chain. Just ask this scientitian.
Seasoning, Rolling and Tying
What are some good things to season my lamb with?
Salt is a must, and just like with steak or a beef roast, the best time to salt your meat is at least 45 minutes before you start cooking it, and even up to overnight if possible (keep it in the fridge uncovered). This gives enough time for the salt to draw out the liquid, dissolve, then re-enter the meat, seasoning it better than if it were just stuck to the surface.
With its robust flavor, lamb takes well to all kinds of spice mixes and aromatics without allowing them to overpower the meat. With a butterflied leg, you want to apply your seasoning the both the inner and outer surfaces before rolling the thing up. Here are a few of my favorite combinations:
- Lots of garlic and oregano or rosemary. Roughly chop a dozen cloves of garlic and a few tablespoons of picked fresh oregano or rosemary leaves in a food processor, then mix it together with a quarter cup of olive oil. Season to taste with plenty of salt and pepper.
- Olives and parsley. Place a cup of good pungent olives like taggiasche or high quality kalamata in the food processor along with a cup of parsley leaves and a few tablespoons of olive oil. Pulse until nearly pureed, then spread the paste all over the inside of the lamb. If you want to get extra pungent, add a half dozen anchovies to the mix as well. You should go easy on the salt because of the salty olives.
- Five spice. Chinese five spice powder with cinnamon, fennel, star anise, Sichuan peppercorn, and cloves provide an interestingly sweet/hot/pungent flavor profile to the meat. I like to add a touch of sugar, soy sauce, and oil to the mix as well to more deeply flavor the meat.
- Harrisa. This spicy North African condiment has a particular affinity for lamb with its heat, vegetal notes, and warm spice background.
- Ras el Hanout. Another North African flavor combination, it's a dry rub that includes cardamom, clove, chili, coriander, pepper, cinnamon, and occasionally floral herbs like lavender or rosehips. You can buy it in specialty spice stores, blend it yourself, or order it online.
OK, so why do I need to tie up my lamb leg?
Because that's what Jesus'd do. If you don't tie up your lamb leg, it won't keep a regular shape during cooking. Irregular shapes lead to uneven cooking. Uneven cooking leads to unhappy bellies. Unhappy bellies lead to lack of familial harmony, and familial harmony leads to ruined holidays. Would you risk ruining a holiday for 5 minutes and the cost of a roll of butcher's twine?
OK, I'm convinced. So how do I do it?
Simple. After laying your lamb out flat and seasoning it, roll it up again with the fat on the exterior, then lay it seam-side-down across pieces of butcher's twine that you've already thoughtfully laid out in parallel lines on the cutting board at one-inch intervals, each piece long enough to tie easily around the roast. Working from the outside towards the center, tie up the lamb. You can show off by using fancy self-cinching butcher's knots, but regular old granny knots (the kind you tie your shoes with) will do just fine.
Your lamb is now ready to cook.
Cooking in the Oven
How do I know when my lamb is done? Can I just follow one of those handy timetables with x minutes per pound?
Absolutely not. Ignore any and every timing chart you've ever seen—they don't work because they don't take into account basic things like shape and fat content, both of which can drastically affect how fast your meat cooks. Instead, get yourself a good instant read digital thermometer.
Doneness levels for lamb are pretty much the same as for beef:
- 120°F (rare): Bright red and slippery on the interior. Abundant intramuscular fat has yet to soften and render.
- 130°F (medium-rare): The meat has begun to turn pink, and is significantly firmer, juicier, moister, more tender, and beefier than either rare or medium meat.
- 140°F (medium): Solid rosy pink, and quite firm to the touch. Still moist, but verging on dry. Fat is fully rendered at this stage, delivering plenty of beefy flavor.
- 150°F (medium-well): Pink, but verging on gray. Moisture level drops precipitously, Chewy, fibrous texture. Fat has fully rendered, and has begun to collect outside the steak, carrying away flavor with it.
- 160°F (well done): Dry, gray, and lifeless. Moisture loss is up to 18%, and fat is completely rendered. What once was lamb, now is dust.
And just like with beef, I personally recommend cooking to at least medium rare—it's hot enough that the abundant fat in the meat begins to melt, lubricating and flavoring the meat. Rare lamb is tougher and less flavorful.
So say I'm cooking it in the oven—what temperature should I use?
Just like with cooking any large piece of meat, you've got a decision to make right off the bat: do you want to cook hot, or do you want to cook cool? Cooking in a high oven will obviously get dinner on the table much faster, but it'll also lead to much more uneven cooking, with the outer layers of the meat overcooking and turning gray by the time the very center is done. Now, I understand that some people don't mind this. I like having some medium-rare juicy meat and some tougher well-done meat on my plate, they say. Those of you who feel this way should be thankful—it makes cooking roasts very easy. Just bang it in a hot oven (around 400°F should do), and roast until the very center reaches the desired temperature.
On the other hand, if you, like me, want your lamb evenly cooked from edge to center, the best thing to do is slow-roast it. Just as when cooking prime rib, the best way to do this is to first place it on a rack in a 200°F oven until it within a few degrees of your desired serving temperature (use that thermometer!). After removing it, crank the oven up as far as it will go, then throw the lamb back in for about 15 minutes before serving in order to crisp up the well-rendered fat layer on the exterior.
So I decided last year to spring for one of those fancy sous vide machines. Can I use that to cook my lamb?
Yes, absolutely. It's one of the best ways to do it. Season your lamb and seal it in a large vacuum-bag, then drop it into a water bath at your desired finished temperature (I go for around 140°F). Since the lamb is so large, it'll take some time to heat through to the center, so you'll want to give this at least 8 hours and up to around 12. Any longer than that, and the meat will begin to turn mushy from the accelerated enzymatic breakdown of muscle fibers. Nobody likes mushy lamb.
Once you've finished cooking it in the water bath, remove it from its bagging, dry it with paper towels, the finish it off just like you would a slow-roasted pice of lamb by banging it in a screaming hot oven for 15 minutes to crisp up the fat.
The meat you end up with is awesomely tender, moist, and perfectly cooked.
Do I have to let my lamb rest just like a steak?
You've been paying attention. Just like with a steak, lamb muscles tighten when they're hot. As they loosen up, their ability to retain their juices increases. This means that more juice ends up in your meat, and less on the cutting board. Allow lamb roasted at high temperatures to rest for at least 20 minutes after removing it from the oven, and meat roasted low and slow to rest for at least 10.
So I'm new to this whole lamb thing—I'm not even sure I like eating the cute little fellas. Is there a way I can jump in the game with minimal effort?
Yep. There are a number of "ready-to-cook" lamb products out there on the market. For instance, Superior Farms offers American and Australian lamb leg in convenient, pre-seasoned, ready-to-cook packages. We cooked a couple of these and tasted them side by side with fresh Colorado lamb.
As far as convenience goes, there's no question: the Superior Farms product is about as simple as it gets. Just take it out of the bag, pop it on a roasting rack, and put it into a preheated oven. A couple hours later, dinner is served.
Flavor and texture, on the other hand, is a different story. The Superior Farms stuff is heavily seasoned with garlic and herbs. Very heavily seasoned—too much so for some tasters. While it's tasty enough, it's difficult to discern that it's even lamb. So much time spent in a cryovack bag with salt also affects the texture of the meat, turning it slightly spongy. It doesn't hold a candle to fresh lamb that you season yourself.
That said, it's a product directly aimed at home cooks who may be intimidated to try roasting a fresh leg of lamb by themselves for the first time, and it that regard, it passes with flying colors. It may be a good option for those just dipping their feet into the other red meat.
So carving boneless lamb is easy—just slice and go—but what about a bone-in leg of lamb?
When you've got a bone-ine leg of lamb, you'll notice that the bone runs along one side of the bulk of the meat. You want to slice from the opposite side. Using a fork or tongs to hold the lamb steady, use a long, thin carving knife to separate the meat into thin slices. Some of these slices may remain attached to the bone, but that's ok. Separate them by then making a single slice across the top and side of the bone. The slices should fall away neatly for you to serve.
I was a Grade A moron and ended up with way too much meat. What should I do with it?
As with prime rib, it's easiest to store leftover roast lamb as one big chunk rather than individual slices, so make sure you slice your lamb to order instead of slicing the whole thing ahead of time. The best way to reheat it is the same way you cooked it: in a low oven until it reaches the desired internal temperature. Smaller pieces work well in a low-powered microwave as well.
Sliced lamb makes fantastic sandwiches. Try it with some good tapenade and spicy arugula greens. Yum!