Preheat the oven to 375ºF. Peel the onion, garlic and ginger, place in a food processor with the cilantro stalks and chilies (seed, if you like) and whiz to a fine paste. Put the spices and curry leaves into a 36 x 25 centimeter roasting pan on a low heat with two tablespoons of oil and fry for one minute, or until smelling fantastic, stirring constantly. Tip in the paste and cook for five 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 eggplants into quarters lengthways, rub and stuff them generously with all the paste, then arrange them in the pan (if using regular eggplants, simply trim then cut into one cetimeter rounds and sandwich the paste between them). Place the pan on a medium heat and fry for five minutes, turning halfway. Add the coconut milk, roughly chop and sprinkle over the tomatoes, season well with salt and pepper, and bring to a boil. Cover with aluminum foil and roast for 40 minutes, or until thickened and reduced, removing the foil halfway. Season to perfection and scatter over the cilantro leaves. Always good with fluffy rice, pappadams, yogurt and extra fresh chili.