If you’re planning a family roast dinner, this slow-roasted leg of lamb is an excellent choice. It’s simple to prepare and yields tender, flavourful meat that practically falls off the bone.
Slow roast the leg of lamb at a low oven temperature for 4 to 5 hours until it is meltingly tender. During the final 30–45 minutes brush on a chutney or similar glaze for a glossy, sticky finish.
Use the stock, vegetables and pan juices left in the roasting tin to make a rich lamb gravy. This method makes for a comforting Sunday roast to share with family and friends.
Every bite of this slow-roasted leg of lamb delivers deep flavour: a sticky glazed exterior and succulent, tender meat inside. It’s ideal for Easter or any special roast dinner.
Try this leg of lamb recipe and you won’t be disappointed. If you want alternatives, you can adapt the same approach to a lamb shoulder, cook a leg of lamb in a slow cooker, or try lamb kleftiko for a Greek twist.
Instructions
Below is the step-by-step recipe. Read the full instructions so you know how to prepare, cook and finish the lamb and make the gravy.
📖 Step by Step Recipe
Slow Cooked Leg of Lamb
Luke and Kay – Flawless Food
The meat becomes so tender it falls from the bone, and the pan juices make a beautiful gravy.
Equipment
Ingredients
- 1.8–2.2 Kg Leg of Lamb (if frozen, defrost overnight)
- 2 Carrots, roughly chopped
- 2 Onions, sliced into rings
- 1 Garlic bulb, separated into cloves
- 4 tbsp Olive oil
- 1000 ml Lamb stock
- 3 sprigs Rosemary
- Salt and pepper
- 3 tbsp Chutney (or similar glaze)
Gravy
- 3 tbsp Plain flour (adjust for desired consistency)
Instructions
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Remove the leg of lamb from the fridge about an hour before cooking. Preheat the oven to 150°C fan / 170°C / 325°F / Gas Mark 3.
Place the onions, carrots, rosemary and garlic in a roasting tin to form a bed for the lamb.
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Place the lamb on top of the vegetables. Rub both sides with the olive oil, season generously with salt and pepper, and leave the fat side up.
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Pour the lamb stock around the lamb, careful not to pour over the top so the meat stays dry on the surface.
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Cover the tin tightly with foil to trap steam. Roast at the temperature above according to weight:
0.8–1.4 kg: 3 hours
1.5–1.7 kg: 3 hr 30 min
1.8–2.2 kg: 4 hr 15 min
2.3–2.9 kg: 4 hr 45 min
3–3.5 kg: 5 hr 15 min -
Remove the foil and brush the lamb with your chosen glaze—about 3 tablespoons of chutney works well. Return to the oven uncovered for 30–45 minutes to brown and set the glaze.
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Take the lamb from the oven, wrap it in the reserved foil and let it rest for at least 30 minutes. Resting allows the juices to redistribute and results in juicier, more tender meat.
Gravy
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Mash the cooked garlic, onions, carrots and any loose veg in the roasting tin and remove excess fat from the top of the liquid.
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Strain the liquid through a sieve into a saucepan and bring to the boil.
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Whisk 3 tbsp plain flour with an equal amount of cold water to make a smooth paste. Add a little at a time to the boiling liquid until the gravy reaches your desired thickness. Season to taste and serve hot.
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Ready to serve with the rested lamb.
Video
Nutrition
Carbohydrates: 5 g
Protein: 41 g
Fat: 18 g
This slow roast leg of lamb recipe was originally posted 23rd April 2020 and updated on 25th February 2025.
Equipment
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Roasting Tin
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Measuring Jug
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Sieve
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Whisk
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Saucepan
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Masher
Ingredients
Here are the ingredients explained in more detail for this bone-in leg of lamb recipe.
Vegetables
Carrots, onions and garlic form a flavourful bed for the lamb. They lift the meat off the base of the pan for more even cooking and also flavour the stock used for the gravy.
You can substitute other root vegetables if you prefer—parsnips, turnips, or celery root all work well and add depth to the pan juices.
Herbs
Rosemary is classic with lamb, but thyme or oregano are good alternatives. For different profiles, try smoked paprika, cumin, or a pinch of cinnamon for warmth. Adjust seasoning to suit your taste.
Leg of Lamb
For the best quality, buy from a butcher, though supermarket legs also work. If using a frozen leg, ensure it is fully defrosted before cooking.
This method works for any size bone-in leg. In this guide we used a 1.8 kg leg. For a boneless leg, reduce the cooking time by around 30 minutes.
Glaze
Adding a few tablespoons of chutney, honey, or a glaze during the last 30–45 minutes creates a shiny, caramelised crust. Use a glaze that contains some sugar or honey for the best result.
Why Slow Roast Lamb?
Slow roasting at low temperature with liquid in the pan creates gentle steam that helps break down connective tissue and keeps the meat moist. Keeping the lamb covered with foil for most of the cook prevents drying and develops deep flavour.
The uncovered final cooking time gives the lamb a browned, attractive finish and enhances texture and flavour.
Cooked this way, the lamb becomes so tender you can pull it apart with forks rather than carving it.
Cooking Time
We used a 1.8 kg leg for these instructions, but the timings below cover a range of weights. Adjust according to your leg’s size.
| Leg of Lamb (bone-in) weight kg and (lb) |
Oven cooking time 170C / fan 150C Gas mark 3 (325F) |
Final cooking time with glaze |
Total cooking time |
|---|---|---|---|
| 0.8–1.4 kg (1.7–3 lb) |
3 hours | 30 minutes | 3 hr 30 min |
| 1.5–1.7 kg (3.3–3.7 lb) |
3 hr 30 min | 30 minutes | 4 hours |
| 1.8–2.2 kg (3.9–4.8 lb) |
4 hr 15 min | 30 minutes | 4 hr 45 min |
| 2.3–2.9 kg (5–6.4 lb) |
4 hr 45 min | 30 minutes | 5 hr 15 min |
| 3–3.5 kg (6.6–7.7 lb) |
5 hr 15 min | 30 minutes | 5 hr 45 min |
How to make lamb gravy from scratch?
This roast produces pan juices and a vegetable stock that make an excellent base for a simple gravy. You only need a sieve, some flour and seasoning.
Strain the mashed veg and juices, bring to the boil, and thicken with a flour paste until the desired consistency is reached.
If you prefer a different sauce, a red wine jus also pairs beautifully with slow-roasted lamb.
Roast Lamb Serving Suggestions
While the lamb rests, prepare roast potatoes, honey-roasted parsnips and steamed vegetables. Yorkshire puddings are a traditional accompaniment, and pigs in blankets are always a crowd-pleaser for children.
Choose a selection of sides—roast potatoes, vegetables and gravy—to create a classic roast dinner your guests will enjoy.
More Roast Dinner Recipes
If you enjoyed this slow roast method, other recipes that use similar techniques include slow cooked rolled lamb breast, glazed gammon joint, and various roast beef joints. For something different try salmon en croute for a showstopping alternative.
Our slow-cooked leg of lamb is a reliably delicious roast that’s easy to prepare and perfect for family gatherings.