Heat pan add 2 tsp oil, sliced onion, red chilli and stir until onion get glassy.

Now add tomato, salt and cook until tomato get mashed. (Allow it to cool down)

Now grind it into fine paste. Add water if necessary.

Now heat pan, add oil, mustard seed, urad dal,  curry leaves and add it into the chutney.

For more recipe https://www.foodloverarea.blogspot.com/