1. You will need a large deep frying pan or sauté pan with a lid or a flameproof and ovenproof casserole dish. Preheat the oven to 160°C/140°C fan/Gas 3.

2. Heat a tablespoon of the oil in the pan. Quickly fry the lamb over a high heat, until golden brown all over – you may need to do this in batches so as not to overcrowd the pan. Remove each batch with a slotted spoon and set aside.

3. Add the remaining oil to the same pan and fry the onions, celery and garlic for a few minutes. Add the spices and fry for another 30 seconds, stirring. Add the stock, tomatoes, tomato purée or paste and the mango chutney. Bring to the boil, stirring, then add the lamb and season with salt and pepper. Stir for a few minutes, then cover the pan with a lid and transfer to the oven for about an hour.

4. Put the pan back on the hob and add the beans and sweet potatoes. Bring everything back up to the boil, then cover the pan again and return to the oven. Continue to simmer for a further 45 minutes or until the lamb is tender and the potatoes are just cooked but still holding their shape. Check the seasoning and serve piping hot.

Prepare ahead: Can be made up to 2 days ahead up to the end of step 3. Reheat, then add the beans and potatoes and proceed as above.