Chef John's Roasted Leg of Lamb

Chef John's technique for deboning and butterflying a leg of lamb is so foolproof that you can do it even if your knife isn't super sharp. For best results, though, watch the video (above) and follow along as Chef John demonstrates the techniques.

How to Debone a Leg of Lamb

A leg of lamb is generally sold without the shank attached. And that is what you want here — one almost whole leg of lamb without the shank attached. The other thing you will need is a knife, preferably a thin sharp knife. But, honestly, you don't actually need a butcher-caliber knife to perform this simple task; you could do it with a wide, less sharp knife just about as well.

The first step here is to remove that one single bone that runs directly through the leg from knee joint to hip joint. When you look at the ends of the the meat, you will see these two joints. Because the bone runs through in a straight line, removing it is particularly straight-forward and easy.

You will be able to feel where the bone is running through the meat. To begin, slice straight into the meat to find the bone. Feel the bone with the tip of the knife.

Then, keeping your knife blade against the bone, cut around the bone, cutting a little bit at a time. Just keep cutting along and around the bone, with the edge of the blade against the bone as much as possible, heading toward one of the joints — it doesn't really matter which direction you head in as you trim away.

Keep cutting along the bone and eventually you'll have cut enough meat way that you can slip your fingers underneath the bone. Then you can also get your knife underneath the bone and begin trimming away towards one of the joints. Cut completely around the joint to free it. Then trim down the bone in the opposite direction to the other joint. And do the same thing, cutting around the joint to free the bone completely.

Congratulations, you have removed the leg! But we're not done yet. There will be a lot of tough connective tissue around where the joints were. Take your knife and cut around this cartilage, tendon, and connective tissue. At this point, your deboned leg of lamb is ready for seasoning and roasting. But we are going to take it to the next stage, which is to butterfly the leg of lamb.

How to Butterfly a Leg of Lamb

The whole idea of butterflying is to get a roast that is about the same thickness all the way across.

To butterfly the deboned leg of lamb, simply open the leg of lamb up: You'll notice that there are two sides to the roast and that one side is significantly larger than the other. Cut into the smaller side first. Slice into the thickest part of that smaller side at about a 45-degree angle, going in a few inches and making small cuts, a little at a time, "unfolding" the meat as you go.

When you've unfolded the smaller side, turn the meat around and do the same thing to the thicker side. Go in at about a 45-degree angle, right into the thickest part of the meat, and because this muscle is a little thicker you'll just make slightly deeper cuts until you've unfolded the thicker side. With both sides folded open, the roast should be more-or-less even in thickness now.