To prepare rasam powder: Dry roast coriander seeds (for powder), cumin seeds (for powder), black peppercorns, toor dal (for powder), and dry red chili in a pan over medium heat until fragrant, about 2-3 minutes. Let them cool completely.
2
Grind the cooled roasted spices from step 1 into a fine powder using a spice grinder. Set aside.
3
Soak tamarind in 50g warm water for 10 minutes. Squeeze the tamarind to extract its pulp, then strain the pulp to remove any fibrous material. Discard the solids.
