Sous Vide Leg of Lamb

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Sous Vide Leg of Lamb is slow cooked in a sous vide water bath until juicy and tender and served with a homemade mint chimichurri. It’s perfect for holidays and special occasions since it feeds a crowd and it’s easy to make with just a few ingredients!

Slow cooking a leg of lamb is a great way to change up your Sunday roast or Easter dinner. You might be intimidated by cooking a lamb leg, but I promise it’s super easy using the sous vide method.

Cooking lamb sous vide style is almost foolproof and effortless, and it turns out moist, tender and flavorful every time. 

What I love most about sous vide cooking is that you get the same results when cooking other cuts of lamb too! 

We love this sous vide rack of lamb, sous vide lamb shanks and sous vide lamb shoulder. They’re always perfectly cooked and never dry or tough!

If you make this sous vide leg of lamb, I highly recommend serving it with mint chimichurri. It’s the same recipe that I serve with these sous vide lamb chops and it’s always a crowd pleaser!

What is Sous Vide?

Sous vide is basically a method of cooking using what is called an immersion circulator. This immersion circulator circulates water in a temperature controlled water bath at a certain temperature to perfectly cook your food every time.

Because the temperature doesn't change, and it keeps your meat (or dessert, veggies, etc.) at the same temperature, your risk of overcooking becomes very minimal.

To learn even more about sous vide cooking, head over and read "what is sous vide cooking."

What is the Water Displacement Method?

The displacement method is where you slowly submerge a ziplock bag in water pushing the air out of the top of the bag (the bag should be slightly open at the top to allow air to escape).

Use a clip (I use binder clips) to clip the bag to the side to keep it from floating and getting air and/or water inside.

Tools Used

• Anova Precision Sous Vide Cooker
• 12 quart container for water bath
• Vacuum sealer
• 16 ounce canning jars

If you don't have a lot of experience cooking sous vide yet, you may want to pop over and read what sous vide cooking is and some tips.

What is the Water Displacement Method?

The displacement method is where you slowly submerge a ziplock bag in water pushing the air out of the top of the bag (the bag should be slightly open at the top to allow air to escape).

Use a clip (I use binder clips) to clip the bag to the side to keep it from floating and getting air and/or water inside.

Tools Used

• Anova Precision Sous Vide Cooker
• 12 quart container for water bath
• Vacuum sealer
• 4 ounce canning jars

If you don't have a lot of experience cooking sous vide yet, you may want to pop over and read what sous vide cooking is and some tips.

Other sous vide recipes

• Sous Vide Veal Chops 
• Sous Vide Venison
• Sous Vide Ribeye
• Sous Vide Sirloin

What is a leg of lamb?

A leg of lamb is a large, lean and expensive cut of lamb. It comes from the two hind legs of a lamb.

Leg of lamb is sold as bone-in or boneless. The top half of the leg is the sirloin half, while the bottom is the shank half. 

Bone-in lamb leg usually weighs about 5-7 pounds, while boneless weighs a little less. The weight actually depends on where the lamb is from. Lamb from Australia and New Zealand is usually smaller than lamb from the United States.

You can also buy lamb leg that has been butterflied. This means the bone has been removed and it has been cut in half. Typically, the leg of lamb is then rolled up, tied and held together by mesh.

Why this recipe works

1. A leg of lamb can be expensive, so you want to make sure it’s cooked right. The sous vide is the perfect way to ensure your lamb is cooked to medium-rare without guessing when it’s done!
2. The sous vide locks in moisture and flavor, so the leg of lamb is juicy, tender and succulent. You never have to worry about dry or tough lamb when using a sous vide water bath.
3. A leg of lamb can feed a lot of people, so this recipe is great for entertaining. It’s also pretty hands off, which gives you time to prepare side dishes like this Instant Pot couscous or garlic mashed potatoes.
4. You don’t need a lot of ingredients and the leg of lamb takes just 6 hours in the sous vide water bath.
5. This lamb is served with an easy mint chimichurri. Mint and lamb are a delicious pairing and this homemade chimichurri is sure to impress your guests.

Ingredients

Please refer to the recipe card below for a full list of ingredients and quantities.

You’ll need a 3-5 pound leg of lamb for this recipe. For the best results, buy one that’s boneless or has a partial bone. Avoid a leg of lamb with the shank attached as it will be difficult to fit in the sous vide water bath.

The lamb is seasoned with 8 smashed garlic cloves, 1 tablespoon of salt and ½ teaspoon of black pepper.

For the mint chimichurri, make sure you use fresh mint and parsley and not dried herbs. Dried herbs will not produce the same texture or fresh flavor.

For the best results, you’ll also want to use a good quality olive oil for the chimichurri.

Step by step instructions

Season the lamb with salt and pepper and let sit in the fridge, uncovered, overnight.

Heat a sous vide water bath to 131F degrees.

Place the lamb in a vacuum seal bag with the garlic and seal.

Cook in the water bath for 6 hours.

Remove the lamb from the bag and pat dry (reserve garlic cloves if desired).

Heat a cast iron skillet or grill over high heat.

Sear the lamb on all sides until golden brown.

Slice and serve with mint chimichurri.

How to make mint chimichurri

Combine all ingredients except the olive oil in a food processor and pulse until everything is chopped. You want it to be slightly chunky, so it doesn't need to be totally blended.

Stir into the olive oil and serve with the sliced lamb.

Sous vide leg of lamb temperatures

The recipe calls for cooking this leg of lamb to 131F degrees, which results in medium-rare lamb. Refer to the table below for more options.  

Sous Vide Lamb Temperature	Doneness
120°F to 127°F	Rare (not recommended)
128°F to 132°F	Medium-rare (recommended)
133°F to 140°F	Medium
140°F to 145°F	Medium-well
146°F and above	Well-done (not recommended)

Expert tips

1. Make sure the leg of lamb you buy fits the size of your sealable bag and water bath. If it’s too big, you’ll need to cut it down to fit.
2. For the best results, buy a leg of lamb with the shank removed. It will be easier to fit in the water bath and to carve.
3. If you only have a butterflied leg of lamb, you’ll want to truss it (roll and tie it) before cooking it in the water bath.
4. For the best sear, pat the leg of lamb dry with paper towels when it comes out of the water bath.
5. Make sure your cast iron skillet is hot before browning the lamb. This will ensure the lamb sears quickly without over cooking.
6. Instead of searing, you can broil the leg of lamb in the oven to achieve the browned crust.
7. Don’t throw out the garlic cloves. Save them to serve with the lamb.
8. When sealing the lamb in the bag, make sure air is removed from the bag so bacteria doesn’t get in.
9. For even cooking, the bag of lamb should be fully submerged in the water bath. To help prevent floating, you can weigh the bag down with something heavy like a sous vide sinker weight.
10. When making the chimichurri, use fresh herbs and don’t over process the herbs as you want the chimichurri to be a little bit chunky.

Common questions

Serving options

Here are a few of our favorite side dishes to serve with sous vide leg of lamb:

• Instant Pot Jasmine Rice or Basmati Rice
• Truffle Mashed Potatoes
• Instant Pot Scalloped Potatoes
• Savory Mashed Sweet Potatoes
• Instant Pot Carrots
• Honey Roasted Parsnips

Did you make this recipe? Leave a comment below and let me know how it turned out!