Pressure cook the dal with turmeric powder and 1/2 teaspon asefeotida powder, water for 2 whistles and mash it. Put the washed sundakkai in a plastic bag close it and give a crush a little with a laddle. Heat oil in kadai, add the mustard seeds, cumin seeds and let them splutter. Now add the chilly, asefeotida powder, curry leaves and onion and saute well. Add the tomatoes and saute till mashed. Add the crushed sundakkai, salt, red chilly powder, sambar powder and saute for 2 minutes. Convert this to the dhal in the pressure cooker, add the tamarind juice. Check salt and taste add enough water and close lid, cook for 1 whistle. Remove cover and boil till the right consistency and convert to serving bowl.
2)Onion dhal chutney:
Heat oil in kadai, add the urad dhal and saute till they turn golden brown. take it out. Add the dry chillies, saute a minute and take it out. Add the onions and saute till they turn light brown. Cool them. In a blender put the onions, chilly, urad dhal, salt, tamarind paste and grind it in to a smooth paste. Convert to a serving bowl. Heat oil in kadai, splutter the mustard, add the asefeotida powder and curry leaves and convert it on the chutney with hot oil. Mix well together and serve..!