A tender and juicy slow cooker leg of lamb is the perfect addition to any special occasion meal.
While it may seem daunting, cooking a leg of lamb in a slow cooker is quite simple!
Slow cooking results in the most tender lamb meat that falls off the bone. Infused with your choice of mint and rosemary flavours and the leftover juices make a lovely lamb gravy.
How to cook Leg of Lamb in the Slow Cooker
This recipe will walk you through everything you need to know about how to cook a leg of lamb in a slow cooker, from choosing the right size leg joint to preparing it for cooking and cooking times.
Check the video below to see all the steps involved.
I will go into more detail throughout the blog post. You can jump straight to the step-by-step recipe below if you don't want to read it.
- How to cook Leg of Lamb in the Slow Cooker
- Slow Cooker Lamb Preparation
- Optional Flavourings
- Do I need to brown the lamb leg before cooking?
- Does slow cooker roast need liquid?
- How Long to Cook Lamb in a Slow Cooker?
- Gravy from Lamb Juices
- Carving Lamb
- Serving Suggestions
- 📖 Step by Step Recipe
- More Lamb Recipes
- 💬 Reviews
Read on to learn everything you need to make slow-cooker roast lamb that will fall off the bone, as seen below.
Lamb has been a popular dish since ancient times, with evidence of lamb consumption dating back as far as 10,000 BC.
The practice of cooking meat in a pot goes back even further, to around 7500 BC.
So let's combine these two culinary traditions by roasting lamb in a slow cooker pot to make tender meat.
Slow Cooker Lamb Preparation
You need to work out how many people you are serving to decide on the leg joint size you need, but also bear in mind the size of your slow cooker pot!
I recommend always using a fresh leg of lamb for this recipe. If using a frozen leg of lamb, always defrost thoroughly before starting to slow cook.
How much roast lamb per person?
As a general guide when buying a leg of lamb, allow 300g per adult. So, for example, if you are cooking for four adults, you would need a 1.2 kg large half leg of lamb.
However, if feeding a family of two adults and two children, a smaller 800 gram joint will be enough for your family.
|Bone in Leg of lamb Kg (lbs)||How Many Adults it Serves|
|600g (1.3lbs)||2 People|
|1.2kg (2.6lbs)||4 People|
|1.8kg (4lbs)||6 People|
|2.4kg (5.3lbs)||8 People|
|3kg (6.6lbs)||10 People|
Another thing to remember is how the joint will fit in your slow cooker (more on this below).
Half Leg of Lamb
A half leg of lamb will fit in most slow cookers. Half lamb legs come from 600kg to 1.2kg and will serve 3-6 people.
There are benefits to both the chump end and the shank end of a lamb leg.
The chump end is the more tender of the two and a better shape for the slow cooker pot. You could even fit two chump ends in next to each other.
The shank end is tougher but has more flavour, and slow cooking will tenderise it beautifully. It is better suited for oval-shaped slow cookers.
Ultimately, your best choice depends on your personal preferences and how you plan to prepare the meat.
Whole Leg of Lamb
If you have a large enough pot and want to feed more people, go for two half-leg joints or a whole leg of lamb, which comes in sizes 1.3kg - 3kg to feed 6-15 people.
It may sound crazy but measuring your pot and taking a tape measure with you to measure the leg of lamb is the best advice I can offer to avoid disappointment!
You may need to ask the butcher to chop the leg bone so it can be folded to fit into the slow cooker.
Help! My Leg of Lamb is too Big for my Slow Cooker
If you can not fit a leg of lamb into your slow cooker pot, worry not. I also have an oven recipe for slow roast leg of lamb.
With just a few key ingredients and a little know-how to preparing lamb for the crock pot, you can easily impress your family with this roast lamb dinner and an absolutely delicious gravy too.For the ingredient measurements and step by steps, click here to go to the recipe card.
Olive Oil or Vegetable Oil
A little drizzle of oil over the lamb helps the salt & pepper to stick; also, use a slight drizzle of oil in the pan when searing the meat.
Salt and Pepper
Season the raw lamb with salt and pepper before browning.
The vegetables are used to raise the lamb joint off the base of the slow cooker pot but also help add extra flavour to the juices, which will be turned into a gravy to serve with your lamb roast dinner.
Cut into chunky rings or halve if they are small onions.
Slice into batons; these can also be served with your slow cooker lamb leg as part of the Sunday Roast.
I like to use garlic cloves for extra flavour. Peel and add them in whole to help add flavour to the stock.
You can add other vegetables to the pot, like turnips, parsnips, potatoes, or sweet potatoes. They all add flavour to the gravy.
We find the stock pots add more flavour than a stock cube. Use beef or chicken stock if you can't find lamb stock.
These can all add extra flavour to the lamb and the gravy.
While the meat is the star of this dish, the herbs help to elevate the flavour.
We use rosemary to sprinkle over the lamb leg. You could replace the rosemary with thyme or oregano instead.
Dried herbs withstand slow cooking times better than fresh rosemary. But you can still use fresh herbs if that's all you have.
Of course, you can skip using herbs.
Mint is a classic flavour that goes beautifully with the lamb; adding a tablespoon of mint sauce to the stock adds flavour and helps produce a killer gravy to serve with your Sunday dinner.
You can substitute 200ml of the water used in the stock for red wine or white wine; make sure to boil it in the pan first to evaporate the alcohol.
Adding a couple of teaspoons of Worcestershire sauce to the stock will impart flavour to the meat and gravy.
Do I need to brown the lamb leg before cooking?
No, you do not need to brown the lamb leg before cooking. However, searing the meat will add extra flavour to the dish and makes it look better once cooked.
If you don't sear it first, you may need to oven-cook it at the end of slow cooking to give it a more traditional roasted appearance. This will take a longer time than searing first does!
Pop the seared meat on the vegetables in the slow cooker pot.
Does slow cooker roast need liquid?
Adding a small amount of liquid when roasting lamb in the slow cooker helps produce steam to prevent the meat from drying out and also creates a lovely gravy to serve with your roast lamb dinner.
You don't want the lamb to sit in the liquid, so don't put too much in.
How Long to Cook Lamb in a Slow Cooker?
The cooking time for a leg of lamb will depend on whether it is a whole leg or half leg of lamb. The good news is, with this great recipe cooking on low, you won't overcook the lamb.
Allow plenty of time before you start slow cooking lamb, as the only way to soft, tender fall off the bone meat, as shown in this blog post, is by cooking at low heat, on low temperature setting.
|Leg of Lamb Size||Low Setting|
|Half Leg of Lamb||7 hours|
|Whole Leg of Lamb||8 hours|
I don't advise on high temperature settings as I have not tried it yet, and everything on our blog is always tested first!
But I think 4-5 hours will give a result that will carve nicely but maybe not fall apart so easily. I will update you when tested.
If you want extra crispy browned skin after slow cooking, put it on a baking tray and roast it for 20 minutes at 180°c fan/ 200°c / 400°F / Gas Mark 6.
Resting Lamb is Important
Once the lamb leg is cooked, always allow it to rest for 30 minutes before carving. This will allow the juices to redistribute throughout the meat, ensuring that each piece is juicy and tender.
This allows plenty of time to make suitable side dishes and gravy to serve with the lamb. Cover the lamb joint with foil to keep it warm.
Gravy from Lamb Juices
No roast dinner is complete without gravy, and this one is incredibly delicious, thanks to the added flavour of the vegetables and herbs.
Remove the carrots; these can be served with the roast lamb dinner. Stain the onions and garlic through a sieve into a pan, ready to create the gravy.
Remove excess fat from the gravy, then thicken with cornflour.
Bring to a boil, and it will thicken nicely, add extra water until at desired texture. Add some browning for a richer colour.
Now you are ready to carve/ pull the meat off the bone. It is so easy to do, you won't even need a knife!
Use two forks to pull the meat into chunks.
Ready to serve.
A Sunday roast is not complete without the perfect sides. Here are some of our favourites to serve alongside a slow cooker leg of lamb.
Yorkshire puddings are the perfect accompaniment to any roast dinner. They are best when freshly cooked and still warm, so make them while the lamb gravy is cooking.
As well as carrots, we like to serve green vegetables such as broccoli and green beans or peas with our lamb roast. Our honey roast parsnips are a great addition too.
Mint sauce is a classic pairing with lamb, and it goes well with this slow cooker recipe. You can add other sauces, like redcurrant jelly or bread sauce, if you want something different.
📖 Step by Step Recipe
Slow Cooker Half Leg of Lamb
- 800 gram Half Leg of lamb
- 2 tablespoon Olive Oil
- Salt & Black Pepper
- 2 Carrots
- 1 Onions
- 4 cloves Garlic
- 1 Lamb Stock Pot Or Beef
- 300 ml Boiling Water
- 1 tablespoon Mint Sauce add to the stock
- Sprinkle Dried Rosemary
- All The remaining liquid from the slow cooker
- 200 ml Boiling Water
- 2 tablespoon Cornflour
- 1 Splash Browning
- Remove lamb leg from the packaging and pat dry with kitchen paper towel.800 gram Half Leg of lamb
- Rub lamb with olive oil and season all over with salt and black pepper.Salt & Black Pepper, 2 tablespoon Olive Oil
- Sear the lamb on all sides until just browned.
- Chop carrots into batons and onion into chunky rings. Place onions in the middle of the slow cooker pot and the carrots around the outside. Peel the garlic and add to the pot whole.2 Carrots, 1 Onions, 4 cloves Garlic
- Place the lamb on top of the vegetables in the slow cooker.
- Mix the stock pot with boiling water Optional- Stir in mint sauce with the stock for minted lamb flavour1 Lamb Stock Pot, 1 tablespoon Mint Sauce, 300 ml Boiling Water
- Pour the stock over the vegetables (not over the lamb leg joint)
- Optional* Sprinkle dried rosemary over lamb for extra flavour.Sprinkle Dried Rosemary
- Place lid on.*Do not remove the lid at any point during cooking*For tender fall off the bone meat cook on low setting.
- COOKING TIMESHalf Leg of Lamb 600g - 1.2kg (1.3lb - 2.6lb)Low for 7 hoursWhole Leg of Lamb 1.3kg - 3kg (2.7lb-6.6lb)Low for 8 hours
- After its had its full cooking time, remove lamb from the slow cooker.
- Optional* If a more crispy skin is wanted, place on a baking tray and you can cook the leg of lamb in the oven uncovered for an additional 20 minutes at 180°c fan/ 200°c
- Cover the lamb joint loosely with foil and allow it to rest for at least 30 minutes to let the juices settle before carving or pulling the meat apart.Enough time to cook your side dishes and make the gravy.
- Remove carrots and cover them to keep warm; these can be used with the roast dinner. They are soft but full of flavour!
- Pour the remaining juices through a sieve into a saucepan to remove onions and garlic.All The remaining liquid from the slow cooker
- Optional* Spoon excess fat off the top.
- Mix cornflour with an equal amount of cold water until lump free. Add to the stock whilst stirring with a whisk.2 tablespoon Cornflour
- Optional* Add a drop of browning for a richer colour1 Splash Browning
- Bring to the boil whilst whisking, lower heat, then add extra hot water until at desired thickness.200 ml Boiling Water
- Once the lamb has rested for at least 30 minutes you can pull it apart with two forks.
- Serve with all the sides and pour the gravy over the top. Enjoy!
Leftover roast lamb can be stored in the fridge for up to 3 days or in the freezer for up to 2 months. Reheat gently in the microwave with some gravy until piping hot before serving.
If you have any gravy left over, it can be stored in a separate container in the fridge for up to 3 days. Reheat until piping hot before serving.
No, you should thaw the lamb before cooking it in the slow cooker.
A bone-in lamb shoulder can be used instead. Use the same cooking time as a lamb leg of the same weight.
More Lamb Recipes
We have plenty of other lamb recipes for you to try.
This slow-cooker lamb recipe is a hearty, delicious meal perfect for any occasion; we hope you enjoyed this recipe. We would love to hear your feedback in the comments.