Start by heating a skillet over medium heat.

Roast the coriander seeds until golden brown.

Once golden, add black pepper and cumin seeds to the skillet and roast until fragrant.

Add the toor dal to the pan and roast until it deepens in color.

Toss in the dried red chilies and toast for a minute or two.

Sprinkle in the turmeric powder and asafetida, mixing well.

Remove from heat and allow to cool completely.

Once cool, transfer the mixture to a spice grinder or blender.

Blend until it reaches a fine, uniform powder.

Store the rasam powder in an airtight container away from sunlight.