Heat oil in a pan. Add mustard seeds,
methi, red chillies and curry leaves. When the mustard splutters, add the coriander, chilli, turmeric powders. Add the onion. Saute till the onions turn brown.
Add the bitter gourd pieces. Sauté for a few more minutes. Add the tamarind juice, salt and the tomato pieces. Close the pan and cook until the vegetables are tender and the gravy thickens.