Roast Leg of Lamb

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This bone-in leg of lamb is rubbed with a Dijon, garlic, and fresh herb paste, then roasted over vegetables so the drippings baste everything. I also include a simple pan gravy made from the roasting juices. It's a perfect main course for Easter, Christmas, and Sunday roasts.

Foolproof Bone-In Roast Leg of Lamb

If you want a holiday roast centerpiece that doesn't require constant attention, this roast leg of lamb is a great choice. Once it goes into the oven, most of the work is done - and you can focus on your guests!

The lamb will turn out juicy and tender with one important condition: use a digital meat thermometer. Lamb doneness is very sensitive to oven variation and the size of the cut. If you don't have a thermometer, get one. It's the single best investment for roasting any large cut of meat.

Roast leg of lamb is not only a stunning and delicious main course - it's also very practical. A 6-pound bone-in leg feeds 8 people easily, and the leftovers are excellent the next day.

The vegetables roast underneath, so you're not juggling multiple pans on the stove. You get both the main course and the side dish ready at the same time.

Why You'll Love It

• Mustard-herb garlic crust. Dijon mustard acts as a binder so the garlic, rosemary, thyme, and oregano cling to the surface of the lamb and don't just slide off in the oven. It also adds a subtle tang that complements the natural richness of the meat.
• One pan, complete meal. The vegetables roast directly underneath the lamb on the same rack, soaking up all the drippings as the lamb cooks. Baby potatoes, carrots, and Brussels sprouts all have similar cook times, which means everything finishes at once. No separate side dishes needed.
• Whole roasted garlic heads. I roast 5 (yes, five!) heads in the pan, which might sound wild, but it's how you get that sweet, mellow, spreadable garlic for serving and for the gravy.

Bone-In vs. Boneless Leg of Lamb

For this recipe, I use a 5-6 pound bone-in leg, which feeds 6-8 people and fits comfortably in a standard roasting pan. When buying, look for a well-trimmed leg with a thin, even fat cap. Too much fat will render off and create excess drippings; too little and you lose flavor and moisture. You can use either bone-in or boneless leg:

• A bone-in leg of lamb is the whole hind leg with the femur intact, usually 5-8 pounds. It's one of the best cuts for roasting. The bone helps conduct heat and provides natural insulation, so the meat cooks more evenly and stays forgiving in the oven. It also makes a more impressive presentation.
• A boneless leg works well, too. Use the same herb paste and oven temperatures, but start checking the internal temperature around 45 minutes. A 4-5 pound boneless leg cooks noticeably faster than bone-in.

Other Ingredients & Substitutions

• Herbs: You can substitute 1 teaspoon of dried for every tablespoon of fresh herbs.
• Dijon mustard: Whole grain or even brown mustard works great! 
• Brussels sprouts: Switch them out with broccoli or cabbage quarters! You can also use asparagus, but don't add those in until the last 10-15 minutes of cooking.
• Carrots: Parsnips, turnips, or any hard squash like butternut, acorn, or kabocha are great alternatives!
• Baby potatoes: Yukon Golds or fingerlings, cut into halves or quarters, are just as delicious.
• Flour: If you're gluten free, you can use corn starch, arrowroot powder or your favorite gluten free flour instead.
• Butter: To make this recipe dairy-free, use ghee or your favorite non-dairy butter.

How to Roast Leg of Lamb

This is a recipe overview. Scroll down to find the complete instructions + ingredient amounts in the recipe card below.

• Prepare veggies: Heat the oven to 450°F. Toss the potatoes, carrots, Brussels sprouts, and halved garlic heads with olive oil, salt, and pepper right in the roasting pan. Spread everything out in one layer (garlic cut-side up), then set the rack on top.

• Prepare the rub: Stir together Dijon + minced garlic + chopped herbs + olive oil to make a paste.
• Prepare the lamb: Season the lamb well with salt and pepper. Rub the paste all over the lamb (I like to cut a few shallow slits first so it really sinks in).

• Set the lamb fat-side up on the rack over the vegetables - those drippings do all the work.
• Roast the leg of lamb: Roast 20 minutes at 450°F, then drop to 350°F and roast until it hits 130°F (medium-rare) or 135°F (medium). If you want a deeper crust, give it a quick 1-3 minute broil at the end. Rest the lamb 15-20 minutes before slicing.

How to Make Gravy From Drippings

Move the veggies out, set the roasting pan on the stove, and whisk flour into the drippings to make a quick paste. Whisk in the roasted garlic, then slowly add beef broth and simmer until silky. Finish with butter, strain if you want it ultra-smooth, and spoon it over everything.

FAQ

Serving Ideas

The classic way to serve leg of lamb is to slice it against the grain on a large platter, arrange it next to the roasted vegetables, and place the gravy in a small pitcher on the side. It looks beautiful without much effort. Here are some other side dishes that will pair well with this meal:

• For bread, I like garlic butter dinner rolls, my homemade bread machine loaf, or garlic bread to soak up the gravy.
• Another traditional pairing is potatoes. Serve the lamb with scalloped potatoes or my garlic-roasted Parmesan mashed potatoes.
• Other roasted veggies that go well with lamb include cinnamon-maple butternut squash with Brussels sprouts, paprika-spiced roasted sweet potatoes and broccoli, and lemon-garlic Parmesan green beans.
• For salad, I recommend my tomato-cucumber-avocado salad or a Greek-style salad. Another great option is a roasted sweet potato and kale salad.
• My roasted asparagus with cheese and bacon is a simple, crowd-pleasing side dish that always gets rave reviews!

More Lamb Recipes

• Lamb Chops with Mustard-Thyme Sauce
• Shepherd's Pie
• Lamb Chops with Cranberry-Balsamic Reduction