Heat oil in a kadai, add mustard seeds, onions, curry leaves and green chillies. Add drumstick, cook for sometime and then add tomatoes and brinjal. Add Aachi Sambar powder, coriander leaves, 750ml of water. Cook with closed lid for 10 minutes. Add tamarind juice followed by dhal and coriander leaves. Finally add salt. Sambar is ready-to-serve.