Grind the onions, garlic and red chili coarsely. Soak the tamarind in little water for 5 minutes. Then strain it. Take the liquid and discard the seeds. Set aside.
Heat oil in pan and fry the ground mixture for few minutes. Add the okra and fry for 3 minutes. Then add the tamarind extract and salt. Mix well. Cover the pan. Lower the heat. Let it cook for about 10 minutes. Garnish with Chopped coriander leaves.