How To Roast Leg of Lamb

Cooking How-To, Cooking Show, How-To
on July 1, 2011
Roast Leg of Lamb
iStock Photo

In this excerpt from my weekely Chef in Your Pocket Facebook Q&A, Relish fan Merry Peterson Luehr needed a reliable way to roast a leg of lamb. So, I broke out my thick glasses, pocket protector and bunsen burner and we got down on some heavy food science!

Q: I've got a 7-pound boneless leg of lamb I want to prepare tonight. Looking online, the roasting instructions are all over the place. What's your opinion?

A: Great question, Merry! Lamb is wonderfully suited for roasting thanks to its high fat content. With most roasted meats, I like to cook slowly to break down tough connective tissues and render fat, then finish with high heat to caramelize all of the sugars and proteins on the surface of the meat. I approach lamb differently, though. Because of its fat content, lamb that is slowly roasted can easily taste almost mushy or soggy…too tender if there's such a thing. So 350F is my magic number for lamb.

Stud the lamb with garlic, rub it down with spices and let it marinate overnight in the fridge. Then, roast at 350F until it's about 135F – 140F internal temp. Let it rest, then carve. Optional: You may also crank the heat up to 400 at the end to really caramelize the exterior of the meat, or finish over smoky hot coals (my personal favorite).

Q: Merry Peterson Luehr: Interesting, most of what of your answers about roasting meat has you starting out screaming hot and then turning it down. True?

A: Totally true! In a sense, it's a good idea, because theoretically, you want to give meats time to relax and rest after cooking, so a lot of folks write recipes that incorporate slow and low towards the end of cooking. I go back to the science. It's just the nerd in me.

Here's the deal. We know we want rich, full caramelization on the outside of the meat. We also know that during cooking, juices come to the surface of the meat and evaporate. Though the water evaporates, fats, sugars and proteins that naturally occur in the meat are left behind on the surface. These are the substances that caramelize for a living! So, rather than force caramelization at the beginning of the cook time with a scorching hot pan and lots of oil when those substances have not yet had a chance to form, I like to cook the meat at a lower temp that's much more conducive to retaining moisture and leave the caramelization for the end.

Some folks would say, "But you're going to dry out the meat with the high heat at the end!" I say, "Not true," because when we wait to brown at the end, it happens fast and fully and doesn't really require much time at all—usually as little as 15 minutes or so. Plus, what's actually browning in this technique are the ultra-flavorful substances from the meat! This crust will taste so much better than what you get from scorching oil in a pan. Make sense? So, it's totally a preference thing, but one that's informed by the food science that's taking place. That's my Mr. Wizard nerd moment for the day!

—By Brian Morris, Chef in Your Pocket