Make some slits on the outer skin of the eggplant. Brush oil on the skin and roast directly over the flame. Roast evenly. Allow the roasted eggplant to cool. Later peel off the skin and mash the eggplant well. Heat oil in a pan under a low flame. Saute chopped onion garlic, green chillies, and tomato. Add red chilli powder coriander powder, salt and water and mix well. Add mashed eggplant to the masala. Add coarsely ground peanuts. Cook well and place in a serving dish. Garnish with chopped coriander.