Wash Tamarind and soak in water for about 2 hours or more. Add water just enough to immerse Tamarind.
Squeeze Tamarind, extract the juice and pulp. Strain the juice, pulp and discard the residue.
Take a pressure cooker, add tamarind pulp with juice and pressure cook for 3-4 whistles. Allow the pressure to release on its own.
For boiled tamarind pulp, add chilli powder, turmeric powder , jaggery, asafoetida, curry leaves,salt and bring to boil
Keep it on low flame, and boil till jaggery dissolves completely. Be careful while boiling as it may splutter.
Whilst, dry roast all the spices listed under dry masala ingredients separately one after the other. Allow it to cool.
Once it cools down, in a blender ground to a coarse powder. Note that it should not be fine or very coarse. It should be blended to medium coarse powder.
Add this coarse blended spice powder to boiled tamarind pulp.
Keeping on a low flame, bring it to boil, stirring occasionally. It will splutter around so use a deep container.
Boil tamarind paste with spices till it thickens and get the consistency of idly batter. Turn of the heat.
In a deep kadai , heat 250 ml of cooking oil preferably sesame oil.
Add mustard seeds, once it splutters add curry leaves, chana dal(optional) , urad dal(optional),asafoetida and boiled tamarind-spices paste .
Mix well and cook on low heat, till oil starts releasing from edges and starts to float above the paste.
Turn of the heat, once it cools down .Store it in a dry airtight glass jar.
Stays good for 6-8 months when refrigerated. Use it as required.