Wash and chop tomatoes & onion. In a kadai, heat 2 tsp of oil and roast red chilly, chana dal, coconut and hing in the same order. Do it till channa dal turns light golden brown color with nice aroma.
Add the onion and saute till golden brown. Add salt. Now add the tomatoes and cook till soft. Remove and cool it down. Add little water & grind it to a paste.
Grind all together in a grinder or use hand blender and blend into the pot.
Tempering / Seasoning
In a small wok, add 2 tsp Oil.
When the oil is smoky hot, add mustard seeds and let them crack, cover half open to prevent the mess here as the seeds will fly all over and the oil will splash. Then add Curry leaves and pour the seasoning on to the chutney.
This chutney can be served with many recipes like Dosa, Idli, Cutlets, Fritters, Vadas, and more. Use as a spread in sandwiches.
Notes
This chutney is prepare with many variations. Coconut can be left out if not available. Some make without onion as well. Sometimes, to make this tangy chutney little sweet, I add a tsp of Sugar and kids will love it.