There really aren’t any fancy moves involved in cooking this iconic spring holiday staple once you understand about lamb and how many ways it can be cut.
First, let’s get through what lamb is. Customers ask for “spring lamb” meaning an animal that is in the 3-5-month-old range. I like to refer to them as milk-fed lambs since ewes will naturally wean off their young by that time. Please do not ask your farmer for a spring lamb and then complain about the fat content. Spring lambs are supposed to have fat. It is when they become “teenagers” between one and two years of age (a.k.a. hoggets) that they begin to grow lean in a gangly fashion at the onset of sexual maturity.
The size of the leg is not always indicative of age. Larger breeds of sheep will produce larger legs. At the same time, there are breeds that even as aged adults would produce a leg roast of only a few pounds. Additionally, there are multiple ways that producers have their lambs butchered leading to assorted sizes in leg roasts. Let’s take a look at them.
Whole Leg Primal
A primal cut is when the butcher breaks down a whole animal into six cuts by first halving and then separating the front, middle and rear sections. A primal leg includes the shank, leg and sirloin, meaning the entire hip bone and ball joint, femur, tibia and fibula. This is a great option for family gatherings requiring a larger roast. Left intact, this is a long cut. To help facilitate fitting into a roasting pan and oven, the tendon between the shank and leg can be severed to allow the shank to bend. However, if you want to use the classic carving method with a manche a gigot (leg bone holder), you will need to leave the joint intact and ask your farmer to have the knuckle end of the shank removed by the butcher.
Whole Leg with Shank
This cut has the sirloin removed down to the ball joint of the leg, but the shank remains attached. As mentioned, the shank can have the tendons cut to allow the joint to bend so it fits into a pan easier. This cut of leg is also a great cut for Passover as the shank can easily be removed and added to the Seder plate.
This cut is traditionally what Americans refer to as Leg-of-Lamb when purchased commercially. There is no sirloin or shank, only the largest muscle group on the upper leg with a single bone (femur) running the length of the roast. The consistency in thickness makes this the easiest to roast and to butterfly.
This is the boneless version of the American Leg or the Whole Leg with Shank. This is also one of the fastest cooking cuts as it can be opened up and laid flat, such as with grilling. Boneless legs are great for stuffing, re-rolling and tying up with string prior to cooking. If you want to try your hand at de-boning your own lamb leg, Saveur has a great little video to show you how. This roast will also be the most expensive option as there were extra costs incurred through fabrication and weight loss with the removal of the bones.
Baron of Lamb
This is the most decadent roast short of an entire young lamb to grace a holiday table. It consists of both rear legs, sirloins and loin, being cut at the point of where the rack begins. In many parts of the world where resources are limited (islands, deserts), the harvesting of very young male lambs is common to reduce the use of resources (milk, grass). It’s a good idea to talk to your farmer now if you want to try this next year.
If you are feeding a large crowd, consider purchasing two smaller legs, a leg and a shoulder or an entire half. With a little planning, the most economical way to serve a large crowd would be to purchase an entire lamb cut to order. This leaves you with a premium holiday meal plus convenient cuts like rib chops and ground or hard-to-find cuts like a whole neck roast, breast and short ribs.
Ah yes…the bones! Both raw and with the bits left over from a well-picked over roast make for excellent bone broth and seasoned stock.
No matter which cut you choose, here are a few tips.
- Allow the roast to come to room temperature prior to cooking to prevent longer cook times and uneven cooking of the meat.
- Skip the marinade. Leg-of-lamb is already a tender cut and does not need the added salt and acid to break down tough proteins.
- Sear for 10 minutes at 450 degrees F and then reduce the oven temperature to 350 degrees F for 10—15 minutes per pound depending on your preference for doneness. Using a meat thermometer, 130-140 degrees for rare, medium at 140-150 degrees and above 150 degrees for well done.
- ALWAYS USE A MEAT THERMOMETER!! Insert to the thickest portion of the roast to test.
- Allow the roast to rest for at least 15 minutes prior to cutting. And when you cut, slice against the grain, meaning you are cutting across the muscle fibers and not along their length.
- For a crispier surface, dry-age the roast in the refrigerator uncovered and patted dry for a few days prior to cooking. Season at the time of cooking.
- Not to discriminate, all this information applies to goat meat, too!