Heat a tawa or heavy-based frying pan (skillet).
Add the dals and coriander seeds.
Dry-roast for about 1 minute, or until light brown.
Heat the oil in a frying pan over medium heat.
Add the dried red chillies, peppercorns and asafoetida and fry for about 1-2 minutes, or until the chillies turn a shade darker.
Transfer all the ingredients to a mortar and pound with a pestle.
Alternatively, grind in a spice grinder, to make a fine powder.
Store in an airtight container and use as required.