Heat oil in a pan.

Add chana dal and urad dal, cook until brown.

Add dry red chillies and coriander seeds.

Add chopped onion and ginger; cook until onion softens.

Add chopped tomato and cook until soft.

Turn off heat and let cool.

Transfer mixture to a mixer grinder and make a paste.

For tempering, heat oil in a small pan.

Add mustard seeds and cook for 10 seconds.

Add curry leaves and asafoetida; cook for 10 seconds.

Add tempering to chutney and mix well.

Serve with dosa or sambar.