Slow Roast Lamb Shoulder on a chopping board

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Lamb shoulder is, in some ways, the underdog of roast lamb cuts. In the UK there are double the amount of searches online each month for a leg of lamb than shoulder. But let me tell you, it can be a true show stopper in its own right when cooked well. Get yourself a good cut and make this slow roast lamb shoulder for a classic Sunday roast or a dinner party… it’s meltingly tender and pulls apart with a fork… not to mention the rich gravy!

How much lamb shoulder do I need per person?

Firstly, this hugely depends on if you have a cut that is boneless or bone-in. And, of course, the appetite of the people you are feeding. For a boneless cut around 200g (7oz) to 300g (10oz) is a good portion per person. For a bone-in cut, I’d suggest around 350- 400g per person.

I’ve included a quick reference table below. You’ll find it hard to find individual shoulder joints that are upwards of 2kg so if you are making for a large crowd you’ll probably need to buy a couple of pieces and roast them at the same time:

Number of peopleBonelessBone-In
2500g – 600g
1.1lb – 1.3lb
700g – 800g
1.5lb – 1.7lb
4800g – 1.2kg
1.7lb – 2.6lb
1.4kg – 1.6kg
3lb – 3.5lb
61.2kg – 1.8kg
2.6lb – 4lb
around 2kg
around 4.4lb

Is lamb shoulder better than leg?

Shredded lamb shoulder on a chopping board with two forks

A good leg of lamb is generally revered as the ultimate lamb cut for roasting. It’s also great for barbequing or stewing. As it’s a leaner cut, it doesn’t hold up so well to long cooking times.

Lamb shoulder is typically cheaper, as it contains more fat, which leads a lot of people to think that it’s an inferior cut. However, when cooked in the right way it is spectacular. Lamb shoulder really needs to be slow-roasted to allow for it to become unbelievably tender. When slow-roasted it is an absolutely amazing joint and the meat practically falls off the bone.

What can I serve it with?

As lamb shoulder is best suited to being cooked as a full piece and slowly roasted it is perfect for a roast dinner. Serve it with roast potatoes, some roasted veg and gravy for a really impressive meal. I like to serve it whole, and shred the lamb at the table on a board.

When slow cooked the meat is so tender that you can also make ‘pulled lamb’ which is great for serving in sandwiches or tacos. Leftovers are something that should happen on purpose with this recipe.

Some great suggestions for side dishes include this roasted garlic tenderstem broccoli or these lemon, thyme and garlic roast potatoes.


Slow Roast Lamb Shoulder Ingredients
  • 1 large brown onion
  • 1 kg lamb shoulder
  • 2 tbsp olive oil
  • few big sprigs of fresh rosemary
  • 1 bulb of garlic
  • 2 tbsp flour
  • 500ml / 2 cups beef stock


You can use thyme instead of rosemary for this recipe if you prefer.

For the gravy, you can use vegetable or chicken stock instead. Or you can swap half the stock for wine for extra flavour.

How to cook it

Aim to take your lamb out of the fridge a good two hours before you are going to roast it as cooking it from room temperature helps the meat cook more evenly.

Turn your oven up to full heat and then start to prepare the lamb. Cut the onion into 6-8 pieces and place in the middle of a deep roasting dish.

Rub the meat all over with olive oil and then place it, fat side up on a chopping board (you may not have a fatty side if you are using boneless). Pierce the meat all over with a knife – going around 1-2 cm deep. Slot slivers of peeled garlic into the hole with a small sprig of rosemary in each. Break up the rest of the garlic bulb and place it in the dish with the onion.

Cover the meat with 2 layers of foil and seal it well before placing in the oven. As soon as you put it in the oven bring the heat down to 170c / 325F. Roast for 4 hours for a 2kg / 4.5lb piece or 3.5 hours for a 1kg / 3.3lb piece.\

Recipe steps 1-4. Place onion in baking dish, stud the lamb fat with garlic and rosemary, place in baking dish and cover with foil

Remove the lamb from the oven and place on a chopping board. Cover with the foil and then place a tea towel over the top. Leave to rest for 30 minutes. While it’s resting make the gravy.

Pour out all but 1-2 tbsp of fat from the baking tray and then sprinkle the flour throughout. Place over medium heat and use a whisk to mix the flour into the leftover bits. Use a potato masher to crush the garlic into the sticky mixture at the bottom.

Pour the stock into the tray and bring to a simmer. Whisk everything together and leave to simmer for 10 minutes. Pour the gravy through a sieve into a jug to serve.

Recipe steps 5-10. Rest cooked lamb, drain fat from baking dish. Add flour to baking dish and mash contents. Add stock and simmer and then strain

Looking for some other great roasts to try? Give this slow cooker pork belly a try!

Products that work well for this recipe:

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Slow Roast Lamb Shoulder on a chopping board

Slow Roast Lamb Shoulder

  • Author: caroline
  • Total Time: 4 hours 15 minutes
  • Yield: 3-4 1x


This slow roast lamb shoulder literally melts in the mouth. It’s a great recipe to impress, and you can literally put it in the oven and forget about it while it cooks! 

The default recipe serves 3-4 people


  • 1 large brown or white onion
  • 1 kg / 2.2lb bone-in lamb shoulder
  • 2 tbsp olive oil
  • few sprigs of fresh rosemary
  • 1 bulb of garlic
  • 2 tbsp plain/all-purpose flour
  • 500ml / 2 cups beef stock


  1. Remove the lamb from the fridge around 1-2 hours before cooking, to allow it to come to room temperature. Preheat the oven to full heat.
  2. Cut the onion into 8ths and then place in the bottom of a roasting dish. Use a dish that is suitable for using on the hob/stove after removing from the oven. 
  3. Rub the olive oil into the flesh of the lamb and season well with salt and pepper.
  4. Using a very sharp knife, make some cuts into the lamb through the fat side, going around 2cm into the meat. Stuff each cut with a sliver of garlic (you may need to cut a few cloves into halves or quarters) and a piece of rosemary. Break up the remainder of the unused garlic bulb and toss it in with the onion in the baking tray (no need to peel).
  5. Place the meat, fat side up, on top of the onion and garlic in the roasting dish. Cover the meat loosely with 2 pieces of foil and then seal it well around the edges of the dish. Place it in the oven and as soon as you do reduce the temperature to 170C/325F.
  6. Roast for 4 hours for a 2kg / 4.5lb piece or 3.5 hours for a 1kg / 3.3lb piece.
  7. Remove the lamb from the oven and place it on a chopping board, covered with the foil and tea-towel. Leave to rest for 20-30 minutes. 
  8. Next, make the gravy. Pour out all but 1-2 tbsp of fat from the baking dish. Sprinkle the flour into the baking dish and use a whisk to mix it into the juices at the bottom. Place over medium-high heat and pour in the stock. Let it simmer for around 10 minutes, using the whisk to mix all the delicious sticky mixture from the bottom of the tray into the gravy.
  9. Finally, use a potato masher to mash in the onion and garlic for full flavour, before straining the gravy through a sieve and into a jug.


  • Thyme can be used instead of rosemary in this recipe
  • Vegetable or chicken stock can be used instead of beef
  • If you are using a bone-in joint then for 2 people use 7-800g/1.5lb-1.7lb. For 4 people 1.4kg-1.6kg/3lb-3.5lb or for 6 people around 2kg/4.4lb.
  • If you are using a boneless joint then you want around 5-600g/1.1lb-1.3lb for 2 people, 800g-1.2kg/1.7lb-2.6lb for 4 people or 1.2kg-1.8kg/2.6lb-4lb for 6 people
  • Prep Time: 15 minutes
  • Cook Time: 4 hours
  • Category: Dinner
  • Method: Roast
  • Cuisine: British


  • Serving Size: 1 (1/4 of the default recipe)
  • Calories: 800
  • Fat: 66g
  • Carbohydrates: 9.5g
  • Protein: 43g

Keywords: roast dinner, lamb, slow-roast, indulgent, meat, entertaining

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