Preheat the oven to 190ºC/375ºF/gas 5. Peel the onion, garlic and ginger, place in a food processor with the coriander stalks and chillies (deseed if you like), and whiz to a fine paste. Put the spices and curry leaves into a 25cm x 35cm roasting tray on a low heat with 2 tablespoons of oil and fry for 1 minute, or until smelling fantastic, stirring constantly. Tip in the paste and cook for 5 minutes, or until softened, stirring regularly. Stir in the peanut butter, mango chutney and tamarind paste, season with a good pinch of sea salt and black pepper, then scrape into a bowl, adding a splash of water to loosen to a paste, if needed.
Leaving them intact at the stalk, cut the aubergines into quarters lengthways, rub and stuff them generously with all the paste, then arrange them in the tray (if using regular aubergines, simply trim then cut into 1cm-thick rounds and sandwich the paste between them). Place the tray on a medium heat and fry for 5 minutes, turning halfway. Add the coconut milk, roughly chop and sprinkle over the tomatoes, season well with salt and pepper, and bring to the boil. Cover with tin foil and roast for 40 minutes, or until thickened and reduced, removing the foil halfway. Season to perfection and scatter over the coriander leaves.
Always good with fluffy rice, poppadoms, yoghurt and extra fresh chilli.