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 as it takes 4 1/2 hours in the oven, but you’ll be rewarded with lamb leg that’s fall-apart tender with an incredible rosemary garlic infused gravy.
After more roast lamb ideas? Browse all my roast lamb recipes or take the Roast Lamb Matchmaker here which will lead you to your perfect recipe!
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.
This recipe is for the other way – long and slow, the sort of meat you pull off the bone with tongs. It’s much easier, less stressful, and you don’t need a thermometer.
And it’s Amazing. With a capital A!
💕 Finding your perfect Roast Lamb recipe! 💕
Not that I want to deter you from using this recipe, but just so you know, I have shared quite a few roast lamb recipes over the years. Because – lamb! How I love thee!
I know it can be hard to choose with so many options so I made a fun (but genuinely useful) Roast Lamb Matchmaker to guide you based on effort level, budget, make-ahead needs, and even cuisines. Because did you know a roasted lamb shoulder reheats 100% perfectly whereas lamb leg is leaner so best served freshly made, even if it’s slow-cooked? 🙂
Take the Roast Lamb Matchmaker here to find your perfect lamb recipe!
How to make a Slow Roasted Leg of Lamb
All the lamb needs is a sprinkle of salt and pepper, drizzle of olive oil, then beef stock/broth and water in the pan which 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!
Roasting bed – Put garlic, onion and rosemary in the roasting pan. This is the bed on which the lamb is roasted and it serves three purposes:
1) to keep the lamb elevated out of the pan juices for even cooking;
2) flavour the flesh that’s in contact with it; and
3) flavours the pan juices which is used to make the gravy.Season – Sprinkle the lamb leg all over with salt and pepper. In this photo, the lamb leg is the right side up which is covered with a thin layer of fat.
Upside down – Turn the lamb upside down and pour the liquids around it. Lamb leg is quite lean so it benefits from slow-cooking submerged in liquid which helps keep the meat moist. If you roast it like a regular lamb leg (right side up, exposes, no foil cover), the meat would end up terribly dry.
Drizzle the surface with oil (just the exposed surface, no need to turn the lamb over).
Slow roast – Roast for 4 1/2 hours at 170°C/325°F (150°C fan-forced) or until the meat on the underside that was submerged in the liquids can be easily pried apart using two forks.
Brown – Turn the lamb over then roast uncovered for 20 to 30 minutes or until it’s nicely browned all over.
The lamb is now ready! But it’s important to rest it for at least 15 minutes before serving which will allow the juices in the meat to redistribute throughout the meat fibres (makes the meat juicier). So transfer it to a platter and loosely cover with foil to rest while you make the gravy.
💡 USEFUL TO KNOW
The lamb will stay warm for 1 1/2 hours so you don’t need to rush the gravy, or worry about rushing to serve it freshly made.
Large roasts usually rest longer (30+ minutes), but because this one is slow-cooked to fall-apart tenderness rather than carved, it needs much less resting time.
How to make the gravy for slow-roasted meat
A great gravy comes down to the flavour in the pan juices and this one knocks it out of the park! All the tasty lamb roasting juices plus the garlic, onion and rosemary is what makes this gravy so good. Here’s how to make it – it’s a cinch!
Heat – Set the pan on the stove with all the liquid that it’s in it, including the garlic and onion which will look like a mushy sludge by now but adds a stack of great flavour into our gravy. Turn the stove on to heat the pan juices then scatter the flour over and mix it in.
Whisk in water then simmer until it becomes a gravy consistency.
Strain into a bowl, pressing all the tasty sludge out of the garlic and onion. (I really need to think of a better word that “sludge” 😆)
Pour into a gravy jug and it’s ready to use!
💡 USEFUL TO KNOW
Leftover gravy keeps in the fridge for 4 days or freezer for 3 months. Use for sausages, peas, chicken, or dress up your mash!
To make it gluten free, just skip the flour and use a cornflour slurry instead. Directions in the recipe card.
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
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)
- 1 1/2 tsp cooking salt / kosher salt (double for flakes)
- 1/2 tsp black pepper
- 1 1/2 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 plain flour (all-purpose flour)
- 1 cup water
- Salt and pepper , to taste
Instructions
ABBREVIATED
- Season leg with salt and pepper, place upside down on garlic, onion and rosemary. Pour liquids in, drizzle with oil, cover with foil. Roast 4 1/2 hours at 170°C/335°F (150°C fan) until meat is pull-apart tender. Flip, return to oven 20 – 30 minutes at 200°C/390°F (180° fan) until well browned. Make gravy while resting.
FULL RECIPE
- Preheat oven to 170°C/335°F (150°C fan-forced).
- Place garlic, onion and rosemary in a metal roasting pan.
- Season lamb: Place lamb leg right side up in the pan. (Note 2) Sprinkle the surface with half the salt and pepper and rub it in.
- Turn lamb over and place it so it mostly sits on the garlic and onion. Sprinkle with remaining 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 1/2 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 the oven and roast for a further 40 minutes or until well browned all over. (Don't increase the temperature as then it doesn't brown as evenly)
- 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 1/2 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. Gluten-free gravy – Skip the flour. Mix 2 1/2 tbsp cornflour/cornstarch with 3 tbsp water and use in place of the flour.
Servings – Allow ~350g/12 oz uncooked bone-in meat weight per person, so a 2.25kg /4.5 pound leg will serve ~6 people. I know this sounds like a lot of meat per person, but you lose more weight with slow cooked meats than roasting leg to blushing pink. plus the bone is sizeable and nobody can carve every scrap of meat off the bone. 🙂
Make-ahead – This is best served freshly made as leg is quite lean so it just isn’t as succulent when reheated. It stays warm for 1 hour so you needn’t worry about being 100% precise with cook timing. Leftovers will keep for 3 to 4 days in the fridge, or freezer for 3 months.
Nutrition per serving assuming 10 servings.
Nutrition – 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 May 2017. Updated for housekeeping matters April 2020 and 2026 – 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…
Just in the oven for our Easter Sunday lunch!!
Smells amazing.
One question do you know if left overs will keep in the fridge, we will have a lot of left over meat 🙁
Gosh yes it will keep for up to 4 days!! N xx
Brill we’re going to make a Thai curry out of the rest…….Bit left field I know!
It was delicious by the way. Definitely will be doing this every time now on.
You can curry ANYTHING. 😂
Hi
I am currently in the process of cooking this for our dinner tonight!
All the stock/water has burnt off after 3 hours of cooking though, is my oven up too high??
X
No! Fat = juiciness and flavour!!! 🙂 N xx
Just cooked and eaten our Easter leg of lamb. It was absolutely delicious with the gravy from the juices. Did it for 4 hours plus 40 minutes browning (2.5kg) as our oven always seems a bit fierce.. Thank you. Recipe is definitely a keeper.
So glad to hear this was enjoyed John! Happy Easter to you too 🙂 N xx
Did this last night. Worked really well. Substituted bottle of red wine for the water!
FANTASTIC to hear Martin!! Thanks so much for letting me know you enjoyed this 🙂 N xx
Hi Nagi, I planned to do a middle eastern recipe from J O. But this morning had a change of heart as my grandaughter is coming for dinner too, she’s 1. So I came across your site and love love love it. Will be doing this recipe now and my dinner worries are gone. Still doing jewelled rice though. I look forward to trying many of your recipes in the future.
One other thing, all the pictures show the bone cut short. Should I do that?
Just cooked and eaten this – delicious!
That’s terrific to hear Neil! So glad you enjoyed this – N x
This is my first time cooking a leg of lamb, I am getting ready to prepare it, is it okay to add Worcester sauce.
Sure thing! Couple of teaspoons will give it a nice edge of extra flavour! N x
Just made this and it was delicious. Everyone liked it and it was polished off. Thank you!
🙌🏻
Absolutely delicious, thank you!
You’re so welcome Jon! Glad you enjoyed it – N x
Can you clarify “right side “? Your note/directions indicate the “upper side is rounder” but your prep pictures seem to show the leg flat side up when covered, then flipped to round side up for final browning. Looks delicious.
Hi Ksk! The flat side is the underside of the leg which is up during most of the cook time so the upper side of the leg is submerged in the braising liquid 🙂 There’s a note in the recipe that explains this a bit and also please see the video! So I rub the top of the leg first, then I flip it upside down and rub then leave it upside down for the baking 🙂 N x
Hi, how long for a 1.854kg weight leg lamb (with bone) please?
HI Lana, please use the cook times for a 2kg lamb per the table in the recipe 🙂 N x
Worked perfectly! Thanks so much! X
Hi Nagi, Can this method to achieve a bit pink in the middle? How should I cook it? Thank you.
Hi Jenny, this method has no pink at all, the lamb is cooked way beyond well done so it becomes ultra tender as you can see in the video. Can’t get lamb that tender if it’s pink! If you want pink, use my Classic Roast Lamb recipe which is linked in this post. 🙂 N x
Hi Nagi, Definitely trying this over the Easter period as I have a leg in the freezer (that’s a lamb leg, not mine). I’m trying out using arrowroot in place of the flour in the gravy hoping that it doesn’t make it too gluggy gluey like.
As one of my sons is a “Creative Director” for an advertising company I’m sure he’d have used Dozer for the ad.
Nagi, this recipe looks amazing! I have a BONELESS 7 lb lamb leg that I’d like to make for Easter dinner. I couldn’t find a bone-in leg anywhere. Any suggestions on how to adjust the coking times? Thanks so much!
Can this be cooked the day before and reheated and if so, what’s the best way to reheat without losing the tenderness?
Prepared this over the weekend. This weeks lunches are gonna be good. Thanks
Hi Nagi,
This looks delicious! Have you ever tried preparing this with boneless leg? If so, how would cooking time/temp vary from above?
Thanks,
Filomena
I think I posted my last comment/question in the wrong place. Please could you tell me how you would cook two lamb legs at the same time?
2 options:
1 larger broiling pot. This is the way I’ve done it before.
2 separate roasting pots. If I ever did 2 again I would try it this way. 1 high heat striving for pink middle, the other long slow roast.
I’ve got an 8 lb leg in the oven now. I used my homemade bone broth, smells divine. My question is, what is the best way to store leftovers. I’ll have a lot since I didn’t expect to cook such a large piece of meat. I can freeze pieces in glass jars with broth. I also have a pressure canner
Freezing with broth is a terrific idea Julie! N xx
If I were to cook two legs of lamb… would the time change? Should I place in same pan or two separate pans? What would you do?
If I could do them on one shelf in a big oven, I would allow 1 extra hour for the covered time 🙂 N x
Made this yesterday and it was delicious! I tweaked it a little bit as I had over 3kg lamb to cook. I did about a liter of beef broth and no water as my roasting tin wasn’t deep enough. I was scared it would over flow and it was the biggest tray I had. I did everything else the same and just didn’t add water to the gravy either or salt or pepper as it was infused with flavour already. It was delicious, the meat didn’t fall off the bone as I’d had hoped, probably because of my dodgy oven but it was soft enough and not chewy at all. On top of that, the gravy was amazing and really was the icing on the cake! Definitely will cook this again. Thank you for the recipe 🙂
I LOVE hearing that Kim! Thanks so much for letting me know! N xx
Do this have to be a bone on or off lamb? I have a boneless leg of lamb to cook for the in-laws tomorrow and I would love to be able to do this recipe. Any help much appreciated. Thanks
Boneless is fine! You can probably cut the cook time by about 1 hour if it’s a butterflied leg 🙂 N x
Sensational recipe! Got a round of applause for this one. Just delicious and so easy to make. The gravy should be bottled. Thank you for sharing this recipe.
I’m so pleased you enjoyed this Heather! Thanks for letting me know! N x