Heat a pan, add a teaspoon of oil and fry the red chillies and channa dal until the dal turns golden brown in colour. Transfer to a plate and set it aside.
Add the onions and fry until transparent and add the tomato and sauté till it turns soft.
Switch of the flame and let the mixture cool down. Then, transfer to the mixer, add red chillies, salt and grated coconut to it. Grind the mixture to a smooth paste, add a little water when grinding.
Transfer to the serving bowl. Now to temper, add oil to a small pan, add mustard seeds and let it splutter. Add the urid dal and curry leaves and sauté for 10 seconds. Pour the tempered mixture to the chutney. Mix well and serve with Idlis or Dosa!