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.
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, 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.
And if blushing pink perfectly roasted lamb is what you’re after, try my Classic Roast Leg of Lamb – and yes, you really need a meat thermometer.
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.
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 of meat slow roasted until the meat is so tender, you can pry it off with a fork, then drown it in a gorgeous gravy infused with garlic and rosemary flavours? THAT you will find here! 🙂
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
More Roast Lamb Recipes
Classic Roast Lamb Leg with Gravy (the type that’s 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 fall apart deliciousness)
Slow Roasted Lamb Shoulder (slow is the only way it should be done!).
A very forgiving, very easy way to roast a leg of lamb. It's not the carving sort - the meat is so tender, you can pull it off the bone with tongs. Lamb leg is actually quite lean, so the best way to slow roast a leg of lamb is to partially submerge it in liquid and roast it covered for most of the time. This way, the flesh is infused with flavour and absorbs moisture. Recipe VIDEO below. Links to more roast lamb recipe in the notes!
- 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 / 750 ml beef broth , low sodium
- 2 cups / 500 ml water
- 4 tbsp / 50g flour (white)
- 1 cup / 250 ml water
- Salt and pepper , to taste
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Preheat oven to 170C/335F (standard) or 150C/300F (fan/convection).
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Place garlic, onion and rosemary in a metal roasting pan.
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Place lamb leg right side up in the pan. (Note 2)
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Sprinkle generously with salt and pepper and rub it in.
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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)
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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).
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Place in the oven and roast for 4.5 hours. (See Notes for roasting time table)
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Remove from the oven, remove foil. Turn lamb over. Check it to ensure the meat is tender (pry a bit off with a fork). If not, return, covered, to oven.
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Return uncovered lamb to oven for a further 45 minutes or until well browned.
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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).
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Use a large spoon to skim off some of the fat from the surface of the liquid.
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Place pan on the stove on medium high. When the liquid bubbles, add flour.
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Use a whisk to mix it in - this may take a few minutes as the liquid reduces.
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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.
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Strain gravy into a bowl, pressing juices out of the onion etc.
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Pour gravy into jug.
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The meat is tender so you will only need tongs to tear the meat off. Serve with gravy.
1. LAMB CUT: This recipe can be made with a leg or shoulder of lamb. Shoulder has more fat running through it than leg, so you can actually roast it uncovered (here's my Slow Roasted Lamb Shoulder recipe), but this recipe will also work with shoulder. This recipe is designed for lamb leg because it's leaner, so it benefits greatly from slow roasting partially submerged in liquid so it doesn't dry out. Cooking it this way also infuses it with flavour.
2. The upper side of the lamb leg has more meat so we want to roast that partially submerged in the liquid for most of the cooking time. The upper side of the lamb is rounder and usually has more fat. The underside has less fat and is more flat.
3. TRY THIS WITH my Truly Crunchy Roast Potatoes!
4. MORE ROAST LAMB: Ultra Tender Slow Cooker Roast Lamb, Slow Roasted Lamb Shoulder, Classic Roast Lamb with Gravy (i.e. it's blushing pink inside) and Slow Roasted GREEK Leg of Lamb (delish lemon garlic flavours!).
5. Roasting Times (this cook method is pretty forgiving so round up to determine cook time eg if your lamb is 1.8kg, use the 2 kg cook times):
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.
WATCH HOW TO MAKE IT
LIFE OF DOZER
The time I had ambitions for him to be the next Kleenex puppy…
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!
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! 🙂
Best lamb roast ever
My leg is only 1.65kgs how much less shall I cook it Nagi … very excited to try tonight!
Hi Cate! Use the 2kg time less 30 minutes for the slow cook time 🙂
Hi Nagi,
I had to write to share that this is the third weekend in a row that I have put this recipe in the oven early on Sunday morning before rushing out the door to take boys to rugby. Late lunch on Sunday is a real treat and the boys lamb and gravy sandwiches for school lunch on Monday are very popular. Love your website and recipes, thank you so much for sharing.
That’s great to hear Tan! So pleased you love this as much as I do – and fits in around rugby runs!!! N xx
Hi – if you are getting a bigger leg (or using 2 legs) to 3.5kg do you need to increase the liquid? If so an equal part of water and broth? How much extra would you need? Thanks
Hi Sally! Use the recipe scaler by clicking on servings and sliding it up until the lamb weight changes to what you are using 🙂 That will change all the ingredients for you!
Nagi, just wondering!! Is it possible to do a roast in a ceramic baking dish as I don’t hav a metal one. Thanks!!
That’s fine Man! Just as long as it fits 🙂 N x
Can I put the oven on a higher temp to cook faster, what temp would you recommend ?
Hi Abby! Unfortunately I don’t recommend that because if the temperature is too high, the meat will cook too fast on the outside and dry it out before the inside is lovely and tender. Sorry to disappoint! 🙂 N x
Thank you so much for a recipe that never fails. Its so beautiful,melt in your mouth and devoured in secs!
Love it!
I love that you love this as much as me! 🙂 N xx
Our family roast is forever changed, Thank you!
I’m glad to hear you enjoyed this Aisha!!! Thanks for taking the time to let me know 🙂 N x
Hi Nagi
Can i cook it one of those oven bags
Absolutely best lamb I had had. The shoulder can sometimes be a little greasy for my liking but the leg was beautiful. First time I have made real gravy and that won the show, thought I’m bad ruined it but it some came back with a little water. Thank you
So great to hear Nick!! Thanks for letting me know you enjoyed this – N x
I’m hoping to make this next week. Can you tell me if it would be okay to use boneless leg of lamb. Seems hard to find bone-in where I live.
That will be fine! It will probably be butterflied ie flatter so you can take 30 minutes to 1 hour off the cook time – just start checking earlier 🙂 (And it stays warm for ages, over an hour – just in case you’re worried about timing it with other things – and also super easy to reheat even in the microwave) N x
Hi, I am in a similar situation to Michael in that I only have a boneless leg of lamb. However, mine is wrapped in a butcher’s net. Will this still be okay?