Sprinkle the aubergine slices with salt and leave for about ½ hour. Then dab off the moisture with kitchen paper.
Fry in hot oil on both sides in a pan. Remove and set aside, then fry the mushrooms, remove and set aside.
Brown the onion slices in a little oil. Add the ginger, garlic, turmeric powder, chilli and lemongrass and fry briefly until it starts to smell. Deglaze with coconut milk and water and bring to the boil briefly. Add the fried aubergine slices and mushrooms, season with salt and pepper, bring to a boil and let the curry simmer gently for 15 minutes. Pour the tamarind juice through a small sieve and squeeze out the pulp a little. Add to the curry with the sugar. Season again to taste.
Serve sprinkled with fried onions or fried onions and chopped coriander leaves.
Serve with rice, Indian flatbread and chutneys or raitas.