Soak tamarind in warm water for 10-15 minutes and extract tamarind water, discarding the pulp
Break each appalam into big random pieces
In a heavy-bottomed pan, add oil and let it heat. Once when the oil is hot add the ingredients under to temper; let it crackle
Add appalam and let it roast in low flame for a minute, sauteeing them between. You need not fry the appalam
Add sambar powder and give a quick stir
Add the tamarind extract, salt and turmeric powder; let it boil for 15 minutes on medium flame, stirring occasionally
Add jaggery, hing and cook for 5 minutes
Finally, make a slurry with rice flour and 2 tablespoon of kuzhambu and mix well. Add it to the kuzhambu and cook for 2 minutes