This Slow Roast Leg of Lamb is going to take your next Sunday roast to a whole new level! It’s ULTRA EASY and very forgiving. It does take patience, but you’ll be rewarded with tender lamb leg that can be pulled off the bone, served with a wickedly delicious rosemary garlic infused gravy.
After more ideas? Browse all my roast lamb recipes!
Slow Roast Leg of Lamb
I’ve said it before and I’ll say it again – lamb leg should either be roasted exactly such that it’s blushing pink inside – either whole or butterflied – or long and slow so it’s ultra tender.
Blushing pink = meat thermometer or holding-your-breath-cross-your-fingers for that moment when you carve, hoping for juicy lamb rather than grey and dry. If that’s what you’re after, use this classic Whole Roast Lamb Leg recipe or my Greek Butterflied Leg of Lamb for a quicker boneless version – and yes, you really need a meat thermometer.
The easier way to roast Lamb Leg
If you’re after a much easier, less stressful way to roast lamb leg, cook it long and slow. You won’t need a knife to carve this. Just pull the meat off the bone with tongs.
And it’s Amazing. With a capital A!
Choose the best roast lamb recipe for you!
Ahhh, lamb, how I love thee! Some people love learning how to do fancy cake decorations. I admire from afar – I highly doubt you’ll ever see a towering 3 tier cake on here.
But big hunks golden brown roasted hunks of meat? THAT you will find here! 🙂 And I’ve shared quite a few roast lamb recipes over the years, so here’s a quick run down on each just in case this slow roasted version isn’t what you’re after:
Roast Lamb Recipes
Slow roasted lamb leg – THIS recipe, a leg of lamb slow cooked until the meat is fall apart tender!
Classic Roast Lamb Leg with Gravy – the classic, perfectly blushing pink inside
Slow Cooker Roast Lamb – fall apart goodness in the convenience of your slow cooker
Slow Roasted GREEK Leg of Lamb – garlicky lemony lamb that is slow roasted until meltingly tender
Slow Roasted Lamb Shoulder – the juiciest, most succulent roast lamb you will ever have!
Slow Cooked Lamb Shawarma – flavour bomb! Your favourite Lamb Shawarma, slow roasted and piled over couscous or stuffed in pita bread
See all Roast Lamb recipes
How to make slow roast Leg of Lamb
The leg of lamb is roasted on a bed of onion, garlic and rosemary which serves three purposes:
to keep the lamb elevated out of the pan juices for even cooking;
flavour the flesh that’s in contact with it; and
flavours the pan juices which is used to make the gravy.
All the lamb needs is a sprinkle of salt and pepper, drizzle of olive oil. Add beef broth/stock and water into the pan (keeps everything all nice and moist + makes pan juices for gravy), cover then slow roast for 5 hours until tender and fall apart.
For an incredible hands-off version of this slow roast leg of lamb, try the Slow Cooker Roast Lamb!
How to make gravy for Roast Lamb
Just set the pan on the stove, mix in flour, then the pan juices and water Cook until it becomes a gravy consistency, then strain. I doubt you’ll need extra salt but add a good grind of pepper if you’re so inclined.
A great gravy comes down to the flavour in the pan juices and this one knocks it out of the park!
Sides to serve with roast lamb
Complete your meal! Here are a few suggestions for sides that go really well with roast lamb:
I promised this was easy, and I meant it. It’s forgiving because if the meat’s not tender enough, you can just stick it back in the oven until it is – and you can cook for even an hour beyond necessary and it’s still going to be juicy.
If the gravy gets too thick, no dramas, just add a splash of water. If the gravy is lumpy, no worries, because in this recipe, it’s strained.
In short – it’s pretty hard to stuff up. If you’re a roast lamb first-timer, just give yourself a couple of extra hours because this lamb reheats great in the microwave or oven, as does the gravy.
Sunday night roast is never going to be the same again! – Nagi x
Just before you go!
Saturday 11 April 2020 – That you are here, looking at this roast lamb recipe for Easter 2020 fills my heart with happiness because it says that you are in some way able to hold onto Easter traditions, despite being stuck at home and unable to celebrate with extended family.
But for many healthcare workers around the world, including my hometown of Sydney, they will be working too hard to celebrate Easter. These brave men and women who are literally risking their lives to save ours.
I feel morally obliged to do something, so I am running a program where you can buy a meal from a local business for our overworked Frontliners. Too exhausted to cook, many are turning to fast food and those who try to cook are faced with empty supermarket shelves.
If you would like to Shout A Meal for a Sydney Frontliner to express your thanks, please click here for my fundraiser and here is more information about my program “Shout A Meal”.
Thank you for reading, and Happy Easter! – Nagi x
Slow Roast Leg of Lamb
WATCH HOW TO MAKE IT
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Slow Roast Leg of Lamb
Ingredients
- 2.25 kg / 4.5 lb leg of lamb , bone in (or shoulder) (Note 1)
- Salt and pepper
- 1.5 tbsp olive oil
- 1 whole garlic head , unpeeled, cut in half horizontally
- 1 onion , quartered (unpeeled is fine)
- 2 rosemary sprigs (2 = whisper of rosemary flavour, 4 sprigs = stronger flavour)
- 3 cups beef stock/broth , low sodium (or homemade)
- 2 cups water
Gravy:
- 4 tbsp flour (white)
- 1 cup water
- Salt and pepper , to taste
Instructions
- Preheat oven to 170°C/335°F (standard) or 150°C (fan).
- Place garlic, onion and rosemary in a metal roasting pan.
- Season lamb: Place lamb leg right side up in the pan. (Note 2) Sprinkle generously with salt and pepper and rub it in.
- Turn lamb over and place it so it mostly sits on the garlic and onion. Sprinkle with more salt and pepper, rub it in. (Video helpful here)
- Add liquids and cover: Drizzle lamb with olive oil. Pour broth and water around the lamb – it won't cover it, that's ok, the lamb sinks into it. Cover with foil (don't use a lid, you want a bit of liquid to steam out).
- Slow roast: Place in the oven and roast for 4.5 hours. (See Notes for roasting time table)
- Check meat: Remove from the oven, remove foil. Turn lamb over. Check it to ensure the meat is tender enough to pry a bit off easily with a fork. If not, return, covered, to oven.
- Brown lamb: Return uncovered lamb to oven for a further 45 minutes or until well browned.
- Rest: Remove lamb, spoon over pan juices generously. Transfer to serving platter, cover loosely with foil while you make the gravy (stays warm for 1 – 1.5 hours).
Gravy:
- Skim fat: Use a large spoon to skim off and discard some of the fat from the surface of the liquid.
- Add flour: Place pan on the stove on medium high. When the liquid bubbles, add flour. Use a whisk to mix it in – this may take a few minutes as the liquid reduces.
- Add water: Once it looks like sludge (see video), whisk in 1/2 – 1 cup of water until it becomes a gravy consistency to your taste. Adjust salt and pepper to taste – I rarely add extra salt.
- Strain gravy into a bowl, pressing juices out of the onion etc. Pour gravy into jug.
Serving:
- The meat is tender so you will only need tongs to tear the meat off. Serve with gravy!
Recipe Notes:
6. Calories in the nutrition are higher than actual because I do not know how to adjust for the fat that is skimmed off the liquid before making the gravy. I usually throw out about 1/3 cup which means the calories is probably closer to 500 calories per serving, and that’s assuming all the gravy is consumed.Nutrition Information:
Originally published Mary 2017. Updated for housekeeping matters April 2020 – no change to recipe!
More Roast Lamb Recipes
I love a good roast lamb – so I’ve shared a few over the years! Here are some of my favourites – or browse the whole recipe collection.
Best of Sunday Supper Roasts
Life of Dozer
The time I had ambitions for him to be the next Kleenex puppy…
The lamb just came out of the oven and the gravy is made. It’s delicious! Thank you for the great recipe Nagi.
Another winner dinner! Served it with your potatoes au gratin (I used sweet potatoes instead) and Greek salad and finished off with your Crème brûlée. Thankyou Nagi😍
Followed to the very letter of the recipe except placed leg of lamb on potatoes which absorbed juices of the lamb. Continued to roast potatoes while lamb rested. Magnificent.
Thanks! N x
How long do I cook a 1kg bone in leg of lamb for
For this slow cook method a 1kg leg would be ready a bit earlier – start checking it at 3 hours and once it is tender (Step 8 in recipe) then you can proceed to the next step. I haven’t tested that size so cannot give you an exact cook time. N x
Hi Nagi! I have a 2.5kg leg of lamb which I have roasting. I have put in a bit late and didn’t realise what the time was! If I increased the temperature slightly and reduced the time, would this still work? If so, what should I put the temperature at and how long should I cook it for?
Hi Nagi, the lamb itself turned out ok although the juices at the bottom of the pan were all burnt and I couldn’t use it as gravy. My leg of lamb was about 2kg and I followed your cooking times exactly. What went wrong?
Made this as specified with a 4.75 lb leg of lamb. It was a hit! Leftovers are going to make a Shepard’s Pie!
Hello, how do I adjust with a boneless leg, 3kg?
Thank you
It should work fine with a boneless leg, just check it as it could take a bit longer as boneless legs cook slower than bone in ones (bones conduct heat to the centre of the meat). N x
Best roast leg of lamb recipe. I do put a domed lid on for the 4.5 hours only to remove it for the last 45 mins having turned the joint over in the liquid, perfect every time.
Great tip! I’ll have to try that! N x
So delicious, my roasts were edible before, but since finding your recipes they’re next level 🤤 I made these along with your crunchy potatoes. Delicious as always!
Hi Nagi. I have a half leg of lamb (weighs just under a kilo) will this work for this sized joint? Should I amend the timings? Hope to hear from you before Sunday!!!!
Hi Sue..notes for a smaller leg are at the bottom of the recipe! Thanks! N x
Hi Nagi. I cooked this yesterday (my half leg weighed just under 1kg) and reduced the cooking time by 3/4 of an hour. The meat was tender, but not “pull apart” tender or slightly pink. There was way too much cooking broth. I know in your reply you say cooking times for a smaller joint are at the bottom of the recipe but I couldn’t see anything for a joint this small. Help and suggestions for my next attempt please?
Hello! Can I make this recipe with a boneless leg of lamb?
Hi Nagi,
I am wondering what your tips would be in terms of making this in advance and then bringing it along with me + reheating at a pot luck?
Thanks in advance!
Hi Kate…this one is absolutely perfect for reheating! Just prepare it as per the recipe and reheat covered with foil then serve with the gravy! Nx
Thank you for responding!
Cooked a smaller lamb leg 1.2kgs for 4.5hrs covered and submerged. Then browned it for 45mins. Turned out very tender and delicious. Thank you
Second time we have done this and it is the BEST roast lamb we have ever had (again). Served it with your mashed and brown sugar carrots -best meal we have had in ages!!!
Hi Nagi. I made this last night and it was superb. what a great thing, to make such a simple recipe that achieves such impressive results. Like all of the recipes I’ve recently tried from this site, super duper. I’m here now looking at a cottage pie recipe for the left overs…
Thanks so much for the whole recipetineats website, its a beauty.
Really excited to cook this! I was only able to get a half leg of lamb…1.3kg
How long should I cook this for? Thanks! Izzy
This is the second time I’ve made this and definitely another hit.
This time I made this in my pressure cooker; set it to high for 90 minutes for a 1.4kg lamb leg (bone-in).
Keep posting and I’ll keep making 😀
This slow roast is divine! Delicious with lovely roast veggies. We will often use a stick mixer are blend some of the onions and garlic into the gravy. A favourite in our house for sure!
Hi, this looks amazing. I have a boneless leg of lamb. Can I use the same technique? Thank you!