Soak the tamarind in a cup of water for ten minutes. And extract the juice for about 1/2 lt. Add salt, sambar powder, curry laves. Heat a little oil. Add mustard seeds. When they crackle, add cumin seeds, dhals, asafoetida and red chillies. Fry them till golden brown and add to the tamarind juice. Allow to simmer for 10-15 minutes. When the gravy gets thickened, disssolve 1 tsp. rice flour in a little water and add. After 5 minutes, remove from the fire. (vegetables like ladies finger, brinjal, potato, onion can also be added, if necessary)