Cut the aubergines into chunks and salt in a colander for 30 minutes to help them soak up less oil.
Heat the oil in a large pan and fry the onion, garlic and ginger until golden. Add the chilli and mustard seeds and toast for one minute. Add the aubergines and the rest of the spices and stir thoroughly to coat. Cook for five minutes, then add the tamarind, tomatoes and coconut milk.
Add enough water to cover, bring to the boil, turn the heat down and simmer gently until the aubergines are tender – about 20 minutes. Check the seasoning and serve with rice or naan bread.
Freezing and defrosting guidelines
Cook as instructed and allow to cool completely. Then transfer to an airtight, freezer-safe container, seal and freeze for up to 1-3 months. To serve, defrost thoroughly in the fridge overnight before reheating. To reheat and serve, place on medium heat, stirring occasionally until the dish is heated through.