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…
Just about to start this for the 3rd time, such a delicious way to roast lamb. Thank you!
Wonderful looking recipe! What suggestion do you have for the beef broth substitute? I have one guest with a beef allergy
This looks delicious! I have a small 2lbs boneless leg of lamb. Should I reduce cooking time to about half of a 4lbs bone in roast? So want to try this recipe and do not want to overcook it.
Hi Shakila! Not half, about 75% of the total cook time should do it 🙂
I have a 7.5 pound leg to roast which your chart suggests will take over 6hrs @ 335. Looking at roasting times for other recipes, I’m seeing 20 -25 minutes per pound at similar temperature which would put my roasting time around 3 hours. I’m struggling to understand why there is such a big difference in roasting times. Can you help me understand the difference. Your results look so good, I want to give it a shot. Thank you.
Hi Dan! I think you can stick with the 6.5lb cook time for a leg that big 🙂 There comes a point when the increase in cook time per extra pound flattens out. The cook times are very different for this recipe because the 20 – 25 min per pound at a similar temp would yield a just cooked lamb leg which is the traditional way to cook this. This one is cooked much longer – beyond well done, until the flesh breaks down and becomes tender as pictured. it’s slow cooked 🙂
Rave reviews from everyone lucky enough to be at dinner today! The meat and the gravy were both delicious. Because the roasting time was so long, I had to start it yesterday and do the last couple hours today. I put the entire roasting pan in the fridge over night and all of the fat collected on the surface so it was easy to remove before going back in the oven for the last couple hours. Thank you for a recipe I will be sure to use many times in the future!
Terrific to hear Dan!! Thanks so much for sharing your feedback – N x
I never comment on recipes, this is actually the very first time but I feel I just have to let you know that I will never make my leg of lamb any other way. Ever. I’ve been using your recipe for a while now and every time it turns out absolutely beautiful. Thank you!
Probably the best roast leg of lamb I have ever made and that is coming from a New Zealander, every on love it, just fell of the bone
This was so delicious and that gravy was next level!
Just made this for the sixth time. Follow the recipe exactly. This is seriously good.
Permission to reprint your recipe & photo(s)? I am pairing roast leg of lamb with our upcoming Syrah release for our wine club members. Your recipe looks amazing. In the wine shipment we include a newsletter and in that is a recipe for pairing with the wine they are receiving. I am happy to give you a credit in print as well as link info to your website.
Thanks for considering this request,
Lynne
Lovely tender melt in your mouth leg of lamb. The gravy is a sensation. Only changes I made were to turn the lamb over for the last 30 mins so the top browned rather than the underside and added 1/2 a cup of red wine and 1/2 a cup of water rather than just one cup water to finish off the gravy. Make sure you skim off the fat before making the gravy as lamb creates a lot of it. Would definitely make this again.
Hi Nagi,
What time should we cook a half leg of lamb(1.1 kg) for?
Absolutely LOVE this recipe. Lamb leg used to be my roast undoing – too many varying thicknesses to get that perfect pink every time. With this recipe, who cares?! I have gotten oodles of compliments from guests whenever I make it, even though we are enjoying it from Saudi Arabia in temperatures of +40 degrees!
Thanks so much for sharing this Nagi, it will be a forever fixture in my kitchen.
Thanks for posting this amazing recipe. I used it yesterday and made the most delicious fall-off-the-bone roast. It tasted so so good and the onion at the bottom thing is a winner for flavour!
I live in Melbourne & its the perfect winter recipe, thank you for taking the time to write out the whole thing, your effort is appreciated
That’s wonderful to hear Charmaine! Thank you for letting me know you enjoyed this! N x
Hi Nagi,
If I want to roast two legs of lamb of 2kg, should I double everything in the recipe? What about the time?
Thank you so much!
PD: I already made one and it was amazing! Inviting more people over next time!
Hi Carmen! Yep double the recipe and squeeze it all in a giant pan or use 2 pans. It will take about 1.5 hours longer (add it to the covered time), from memory. But check it every now and then – just pry a bit of meat off to see how tender it is 🙂
Hi Nagi, I was wondering if I could add wine instead of some of the water? If so, would you recommend red or white?
Thanks so much!
I would like to know this aswell. I have red wine to add and but don’t know quantities I should use? I am cooking this for dinner tonight 🙂
I’m so sorry for the late reply! You can sub ALL the water with white OR red wine, it will be amazing! N x
Nagi, this roast was AMAZING! I bought a leg from Woolies that was close to 3kg. Set my alarm and put this in the slow cooker at 5am. We had friends over for dinner that night. Everyone loved it! We all ate way to much lamb, than what was good for us, and the bonus was that I had left overs for truly awesome sandwiches, the next day. Thank you, thank you. Definitely making this again and again.
That’s so great to hear Leanne! Thanks for letting me know you enjoyed this! N x PS I am far to familiar with the excess lamb eating feeling…..
I cooked the roast upside down! Only just realised when flipping?! Have I ruined it?
Hi nagi how long will a 10 lb bone in leg of lamb take?
Are you sure it’s LAMB??!! 😳
Yes I’m sure it’s lamb! It’s a leg of lamb with the bone and all it weighs roughly 9 pounds I’m sure if I remove the bone it will b about 8 but I’m not planning on having the bone removed
OMG that’s giant! I am guessing 12 hours 🙂 N x
Really excellent method, roasts have changed forever. I combined this with your yummy potatoes (with polenta crust) as well. FWIW I chucked some carrots in the liquid when turning the roast with half an hour to go, then put those carrots in with some pumpkin when the potatoes went into the hot oven.
I might try roasting with the fat cap up next time but otherwise stress-free and so delicious, thank you
That’s great to hear Dav! Thanks so much for letting me know you enjoyed this! N x ❤️
Dear Nagi,
What is the recipe for the beef broth? Thank you.
I’m afraid I don’t have one on my site yet! 🙂