One Pan Roast Leg of Lamb is an easy and flavorful recipe perfect for Sunday lunch, Easter, or holiday meals. This oven-roasted lamb dish is cooked with potatoes, carrots, parsnips, radishes, and green beans, all seasoned with herbs and roasted together for maximum flavor. Using just one roasting pan, this recipe minimizes cleanup while delivering a tender leg of lamb with crispy, golden vegetables. Ideal for family dinners or meal prep, this classic lamb roast is a great choice for feeding a crowd with minimal effort.

A classic roast dinner made simple. This one pan recipe features juicy leg of lamb roasted alongside seasonal vegetables, all infused with herbs and meat juices for a deeply flavorful, no-fuss meal.

Ingredients

For the Lamb:

2 kg (4.4 lb) leg of lamb
1 tbsp olive oil
½ tsp salt
½ tsp black pepper
½ tsp dried rosemary

For the Potatoes:

4 medium potatoes, scrubbed and chopped into large chunks (no need to peel)
2 tbsp olive oil
¼ tsp salt
¼ tsp black pepper
½ tsp dried thyme

For the Remaining Vegetables:

3 carrots, peeled and chopped into bite-sized chunks
3 parsnips, peeled and chopped into bite-sized chunks
10 large radishes, halved
150 g (5.2 oz) runner beans, sliced
100 g (3.5 oz) extra fine green beans
¼ tsp salt
¼ tsp black pepper

Instructions

Preheat the oven to 180°C (350°F).
Prepare the lamb:
Place the leg of lamb in a large roasting tin. Lightly score the fatty parts with a sharp knife. Rub with olive oil and sprinkle with salt, pepper, and rosemary.
Roast the lamb:
Roast in the preheated oven for 1 hour 15 minutes.
Add the potatoes:
After 1 hour 15 minutes, baste the lamb. Arrange the potatoes around the meat, drizzle with olive oil, and season with salt, pepper, and dried thyme. Return to the oven for 15 minutes.
Add root vegetables:
Remove the tin, turn the potatoes, and add the carrots, parsnips, and radishes. Toss in the meat juices and roast for 25 minutes.
Add the green vegetables:
After 25 minutes, add the runner beans and green beans. Stir gently to coat with juices. Sprinkle with salt and pepper and return to the oven for a final 15 minutes.
Serve:
Transfer the lamb and vegetables to a warm serving platter. Rest the lamb for a few minutes before carving.

Tips

Score the lamb to allow seasoning and heat to penetrate the fat layer.
Use a meat thermometer for perfect doneness: 60°C (140°F) for medium-rare, 70°C (160°F) for medium.
Let the lamb rest for at least 10 minutes before carving to retain juiciness.

Variations and Substitutions

Different vegetables: Swap parsnips for turnips or butternut squash, or use sweet potatoes instead of white potatoes.
Fresh herbs: Replace dried rosemary and thyme with fresh sprigs for more aromatic flavor.
Lamb shoulder: Can be used instead of leg, though cooking time may increase slightly.
No runner beans? Use broccoli florets or courgettes added during the last 15 minutes.

FAQs

Can I prepare this in advance?
Yes, prep all vegetables and season the lamb ahead of time. Refrigerate, then bring to room temperature before roasting.

Should I cover the lamb while roasting?
No, roasting uncovered helps the fat crisp up and browns the vegetables better.

Can I use bone-in lamb?
Yes, but cooking time will be slightly longer. Use a thermometer for accurate results.

Serving Suggestions

Serve with mint sauce or a rosemary-infused gravy.
Add a side of Yorkshire puddings or crusty bread to soak up the juices.
Pair with a bold red wine like Shiraz or Cabernet Sauvignon.

Why You’ll Love This Recipe

A complete meal cooked in one pan—less prep, fewer dishes
Combines tender meat with crisp, flavorful vegetables
Perfect for family gatherings, Sunday roasts, or holiday dinners
Easy to customize with your favorite herbs and vegetables
Impressive yet approachable for home cooks