Heat 1 teaspoon (tsp.) of oil in a pan add pigeon pea, Bengal gram, black gram, coriander seed, asafoetida, dry chili until the grams turn golden brown. Remove from fire cool down and Grind them into a fine paste by adding little water as needed.
Mix the tamarind juice and ground paste to a think pan and bring to boil and cook until the raw smell goes away.
Temper (fry mustard seed until stop splattering in a pan in oil) the mustard seed and add to the boiling kuzhambu and serve.