Spiced lamb pie with chickpea and potato mash

Method

1. Preheat the oven to 150°C/fan130°C/gas 2. Put the lamb in a roasting tin. Mix 50g of the butter with half the ground spices and all of the garlic. Season well and spread all over the lamb. Cover the tin with foil, then roast for 3-4 hours until the meat is falling away from the bone.
2. Meanwhile, heat the oil in a large pan and fry the onions over a low heat for 15 minutes until soft. Add the remaining spices and cook for a few more minutes. Add the tomatoes, chicken stock, sultanas and cinnamon stick, then season well. Simmer for 20-25 minutes until thick. Remove and discard the cinnamon. Allow the sauce to cool a little, then stir in the yogurt and fresh coriander.
3. When the lamb is nearly ready, put the potatoes in a pan of cold salted water, bring to the boil, then simmer for 20-25 minutes. Drain well and return to the pan. In a small pan, warm the chickpeas in a splash of stock, then mash using a masher or hand blender. Stir the mashed chickpeas into the potatoes, then mash with the remaining butter and the double cream. Taste and season.
4. Once the lamb is out of the oven, put it on a board and shred with 2 forks. Skim the fat off the juices in the roasting tin and discard, then add the juices to the tomato sauce. If cooking the pie immediately, turn up the oven to 180°C/fan160°C/gas 4.
5. Mix the shredded lamb with the sauce, spoon into a 2 litre pie dish, then top with the mash.
6. To cook, dot the top of the mash with extra butter, then bake for 25-30 minutes until golden and bubbling.