Slit the bitter gourds vertically and scrape out the seeds and slice. Mix together refined flour and little salt, apply this mixture to the bitter gourds and set aside for half an hour. Wash them and drain well.
Heat oil in a non stick pan and add mustard seeds. As they splutter add garlic and sauté for a minute. Add onions and sauté until they turn golden brown.
Add red chilli powder, turmeric powder and coriander powder and mix well. Add bitter gourds and sauté for two minutes.
Stir in tamarind pulp, jaggery water and salt. Cover and cook for twelve to fifteen minutes or until the bitter gourds are tender.