Mustard, black gram dhal, Bengal gram dhal, Curry leaves.
1. Cook potatoes in pressure cooker.
2. Peel the skin and mash it.
3. Cut onions and chilles into thin long slices. cut tomatoes finely.
4. Heat oil in a frying pan, add the seasonings, when it splutters add onions, chilles, fry till light brown.
5. Put tomatoes and fry for two more minutes.
6. Add thick tamarind extract, salt, turmeric powder and half a cup of water.
7. When it starts boiling add mashed potoates.
8. Stir well and reduce the flame.
9. When the masala becomes thick, remove from fire and serve hot.
10. Lime juice can be substituted for tamarind, which can be added just before removing from fire.