Roast Leg of Lamb


Classic roast leg of lamb recipe. Leg of lamb marinated in a citrus rosemary marinade, then oven seared and slow roasted.

Photography Credit: Elise Bauer

The most important thing to remember about cooking a lamb roast is to not over-cook it. Lamb has such wonderful flavor on its own, and is so naturally tender, that it is bound to turn out well, as long as it is still a little pink inside.

How to Cook a Leg of Lamb

There is some debate over which method yields the best results—slow cooking at low heat the entire time, or searing first on high heat and then slow cooking. James Beard in his American Cookery prefers the slow-cook-low-heat method (he rubs the roast with salt and pepper and cooks it at 325°F the whole time.)

We generally get great results with the searing method, starting at high heat and then dropping the temp which is the method described in the following recipe.

If you use searing method, you will have ends that are more well done, and as you get closer to the interior, more rare. This way you have a variety to serve to guests.

Another point where there are wildly varying opinions is the internal temperature that constitutes “medium rare”. I’ve seen references that range from 120° to 145°F.

For this roast, I pulled it out at 125°F. As it rested the internal temperature continued to rise a few points as the meat continued to cook.

Sliced Roast Leg of Lamb with pink center

Use a meat thermometer

We like our roast leg of lamb on the rare side of medium rare, and this roast was perfectly done to our taste. Clearly an accurate meat thermometer is essential, and it helps to insert the meat thermometer at different places into the deep interior of the roast to get a good read.

A great way to keep tabs on how well the roast is cooking is to use a remote thermometer. This way you can tell when the roast is done without having to open the oven door, avoiding the loss of heat that comes from doing that.

Let lamb roast sit at room temp before cooking

The directions that follow in this leg of lamb recipe assume that you have let the roast sit at room temperature for an hour or two before roasting. If you are taking a roast and cooking it directly from the fridge, it will take longer to cook.

Updated from the recipe archive, first posted 2006.

Roast Leg of Lamb Recipe

  • Prep time:
  • Cook time: 1 hour, 30 minutes
  • Marinating time: 2 hours
  • Yield: Serves 8 to 10

The marinade we used on this roast comes from my friend Suzanne and it works quite well. A simpler marinade of rosemary, extra virgin olive oil, garlic, pepper, and lemon juice would do the trick quite nicely too. One can also make tiny slices into the surface of the roast and insert slivers of garlic and herbs.



  • 1/2 cup orange juice
  • 1 cup white wine
  • 3 cloves garlic, minced
  • 2 teaspoons of fresh thyme or 1 teaspoon of dried thyme
  • 2 Tbsp of fresh chopped rosemary or 1 Tbsp of dried rosemary
  • 1/4 teaspoon of fresh ground pepper

Blend marinade ingredients in a blender, just a few pulses until well mixed.

Lamb Roast

  • One 6-pound leg of lamb, bone-in or boneless. (If boneless, the leg should be tied up with kitchen string by butcher.)
  • Marinade
  • Salt and freshly ground black pepper

Special equipment:


1 Marinate lamb: Place lamb and marinade into a plastic bag. Squeeze out as much of the air as possible from the bag and seal. Wrap again with another plastic bag to ensure that the marinating lamb doesn't leak.

Marinate for several hours, or overnight, in the refrigerator.

Remove the lamb, still in its marinade bag, from the refrigerator at least an hour (preferably two hours) before putting in the oven to help bring the lamb closer to room temperature before roasting.

2 Preheat oven and arrange racks: Preheat oven to 425°F. Arrange two racks in the oven - a middle rack to hold the lamb, and a lower rack to hold a roasting pan with which to catch the drippings.

Note that this arrangement of racks and pans, with the roast sitting directly on the oven rack, will create a natural convection of heat in the oven, causing the roast to cook more quickly than if cooked the traditional method in a rack in a roasting pan.

3 Season lamb and place in oven: Remove the lamb roast from its marinade bag (you may want to temporarily place lamb in another roasting pan, just to make it less messy to work with.) Pat dry the marinade off the lamb with paper towels.

Generously salt and pepper all sides of the roast. Arrange the roast fattiest side up, so while the lamb is cooking the fat will melt into the meat.

Place the roast directly on middle rack of the oven, with a roasting pan on a separate rack a rung lower, to catch the drippings. You may also want to put some water in the bottom roasting pan, so that the drippings fall into the water instead of burning in the hot pan and smoking up your kitchen.

4 Roast: Roast at 425°F for 20 minutes. Then reduce the heat to 300°F and roast an additional 40 minutes (for a 6 pound boneless roast) to an hour (for a 6 pound bone-in roast).  If you are cooking a roast bone-in, the bone will act as an insulator and will require a longer cooking time than a boneless roast.

In general estimate 10-13 minutes per pound for total cooking time (for rare), including that first 20 minutes at high heat. (Assuming you let the roast sit out for an hour or two before putting it in the oven. If it's right out of the fridge, it will take longer to cook.)

Note that the method of cooking directly on the oven rack will mimic a convection oven and the cooking time/oven temp needed will be less than you would need if you cooked the roast on a rack in a roasting pan. If you are cooking the roast directly in a roasting pan, rack or not, start the roast at 450°F and after 20 minutes reduce the heat to 325°F.

Also, the shape of the roast will have an impact on the cooking time. Our roast was rather long and thin, so it cooked up fairly quickly. A thicker roast may take longer than expected.

So, use a meat thermometer!

About 20 minutes before you expect the roast to be done, start checking the meat thermometer. Note that every time you open the oven door, you'll need 10 minutes or so to bring the oven back up to temperature, thus slowing down the cooking process. So, don't check too often, or use a remote meat thermometer. Remove the roast from the oven anywhere from 125°F to 135°F for medium rare. Lamb should never be cooked until well done or it will be too dry.

5 Let rest: Let stand for 25-30 minutes before carving (so the juices don't all run out when you cut into it). Cut away the kitchen string and slice with a sharp carving knife, 1/2 inch thick slices, against the grain of the meat.

6 Collect drippings for gravy or sauce: While the roast is resting, use a metal spatula to scrape up the drippings in the roasting pan. Use the drippings to make a gravy, or use just the drippings themselves to serve with the lamb.

Serve with some mint chimichurri or homemade mint jelly.

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James Beard's Roast Leg of Lamb Recipe from Epicurious


Elise Bauer

Elise Bauer is the founder of Simply Recipes. Elise launched Simply Recipes in 2003 as a way to keep track of her family's recipes, and along the way grew it into one of the most popular cooking websites in the world. Elise is dedicated to helping home cooks be successful in the kitchen. Elise is a graduate of Stanford University, and lives in Sacramento, California.

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62 Comments / Reviews

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Did you make it? Rate it!

  1. [email protected]

    Sorry. My gas stove has perfect temperature. Following this recipe will give you an inedible result. Way to low a temperature and cooking time.
    Try broiling first and 30 min at 350 or 400.

    It was raw the time I tried to follow

    Show Replies (1)
  2. Michael

    I made this for Christmas dinner. It turned out fantastically. My only quibble was that it cooked way faster. But I think that was because my bone in leg of lamb had a lot of bone. My kids loved it. My wife loved it. And I thought it was the best thing I’ve ever made thank you


  3. Lyda

    It came out great! My leg was semi bone less, I made it on Dec 22 to celebrate my husband’s birthday. I added olive oil to the marinade and also rubbed it on the outside before roasting. I also inserted garlic slivers and rosemary sprigs all over the meat! It came out great… had a little trouble with the mint chimichurri, maybe I used too many herbs because I had to almost triple the olive oil so it would look like the one in the picture. Everyone loved it and I will sure make it again! Thanks Elise!


  4. Mary

    Glad I saw this as I have a boneless leg of lamb in the freezer for Easter.
    I’d like to BBQ — along with some salmon for the non meat eaters. I
    won’t get gravy from the lamb by doing this so what can I serve that
    would that would go with both lamb & salmon? If that isn’t possible —
    what would be a good sauce for a BBQ lamb?

    Thank you!

    Show Replies (2)
  5. Herb

    This past Easter, my wife suggested we try something different than what we’ve had every year.
    So, we got a whole leg of lamb, bone-in. I watched a video online for how to bone it out, and I did it perfectly on my first try.
    You have to make sure you get the musk glands out of it as you bone it. There are 2 of them, so make sure you get both of them.
    If not, you are in for some nasty leg of lamb.
    Anyway, I boned it out, cooked it in the oven with some Moroccan spices, and it turned out to be our new go to Easter meal from now on. The sweet spices are very aromatic, and the warm spices add a depth of flavor you should not miss.

    I did not marinate it in anything other than liberal amounts of EVOO, and salt, black pepper, rosemary, and thyme.
    I cooked it with cinnamon, turmeric, nutmeg, a small pinch of cloves, and some Sriracha sauce mixed together.
    The results were outstanding & our guests were asking for my recipe.
    We will be having this again soon.

    Thanks for all the great recipes Elise.

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Sliced Roast Leg of Lamb with pink centerRoast Leg of Lamb