In a bowl add toor Dal, channa dal and red Chilli. Soak atleast for 2 hour

Strain the water. Add salt and hing to dal mixture and grind it into coarse mixture. If required sprinkle very little water

In a pan add coconut oil and the oil is hot add mustard seeds, curry leaves, red Chilli and do the tempering. Add hing and switch off. Transfer it to the small bowl

The same pan add coconut oil, ground mixture and turmeric powder. Cook in low flame for a minute or until it become to the right consistency to make balls. Switch off and let it cool down

In the mean time add coconut, green chili, cumin seeds, ginger and little water to a mix me jar and grind it

Add thick curd, water, salt, rice flour and turmeric powder to the mixie jar and grind it once

Make small Urundai with the lentil mixture. Grease the idli thattu with little oil and place the Urundai

Steam the Urundai for 5-6 minutes and let it cool down

Add the buttermilk mixture, cooked Urundai into the pan and boil in low flame for 3-4 minutes or let’s it bubbles up and starts boiling

Switch off and add the tempering