Soak the tamarind and extract thick pulp.
Heat a nonstick pan, add oil and temper with mustard, chana dal, hing, curry leaves, green chilli, ground nuts, cashews and saute for couple of minutes
Add the tamarind extract and add to the pan. Add water as required. Add turmeric powder and salt, bring to a boil
Cook on high for 10 mins, then simmer till the paste becomes thick.
Add the spice powder and mix well.