Roast the Eggplant: Preheat the oven to 400°F (200°C). Roast the eggplant for 40-45 minutes until charred and soft. Let it cool, peel the skin, and mash the flesh.
Cook Aromatics: Heat oil in a pan. Add cumin seeds, then sauté onions until golden. Add garlic, ginger, and green chilies. Cook for 1-2 minutes.
Add Tomatoes and Spices: Stir in tomatoes, turmeric, coriander powder, and salt. Cook until the mixture thickens.
Combine with Eggplant: Add the mashed eggplant and mix well. Cook for 5-7 minutes. Sprinkle garam masala and cilantro.
Serve: Garnish with extra cilantro and serve hot with roti or rice.