Vegetarian tamarind curry

Boil the potatoes in salted water for 15 minutes, or until very tender. Drain and cool slightly. Once cool enough to handle, break up into jagged, bitesized pieces; set aside.

Meanwhile, heat the ghee in a large pan over a high heat, then add the mustard seeds. Once they pop, add the asafoetida and curry leaves. Fry briefly, then turn down the heat and add the cinnamon and cumin seeds. Crackle briefly, add the peanuts and stir fry for a few minutes until lightly browned. Add the ginger and chillies and fry until fragrant (1-2 minutes), then stir in the tomato purée, tamarind, sugar and passata. Cook until bubbling, then add the cooked potatoes, stirring gently until coated. Cover and cook for 5 minutes, then scatter over the coriander and serve with chapatis or naan.