I roast my whole eggplant on a grill or my toater oven.Then peel the dry skin.Mash it well.In a pan saute chopped onion,ginger and garlic and add tomatoes.Add spices as per taste"(I add Indian spices).Then Add mashed eggplant and salt.(green chillies add nice flavor).Garnish with Cilantro leaves.Serve with bread or rice.