Heat oil in a pan or a kadai.
Add the balck gram, Bengal gram, sliced onions, red chillies and jeera.
Add salt.
Continue to saute.
Add more oil, if it is too dry.
Once the onions are soft and brown, put in a blender.
Add the coriander leaves and water.
Grind it to a fine consistency.
:- Onion Chutney is ready,
:- Serve Onion Chutney with dosa or idli.