This is an interesting combination of coconut, mustard seeds, and roasted eggplant. I fondly think of it as the South Indian version of the North Indian baingan ka bharta.
Roast the eggplant over a medium gas flame or a charcoal grill, turning it frequently with tongs, until the inside is soft and the skin is completely charred on all sides. Let cool, then peel and mash. Put the eggplant in a deep bowl.
Put 3 of the chiles, ½ teaspoon of the mustard seeds, the coconut, garlic, ½ teaspoon of the salt, and