Slice a deep cross in the round end of each aubergine. Soak in heavily salted water for 30 minutes, then drain and pat dry. Fry in a tablespoon of the oil for about five minutes, then drain and set aside.
Dry-roast the coconut, peanuts, sesame, coriander and cumin seeds for 30 seconds, until fragrant. Cool, then blitz in a food processor with the chilli, fresh coriander and a little water.
Over a medium heat, fry the mustard seeds and curry leaves in the remaining oil for 30 seconds. Add in the onions and cook for 10 minutes. Add the ginger, garlic, turmeric and chilli powder, followed by the coconut milk. Bring to the boil, turn down to a simmer, cover and cook for 20 minutes until soft. Season to taste with salt and the chutney. Add the aubergines to the sauce and cook for 10 minutes. Garnish with fried onions and curry leaves to serve.