Soak the arhar ki dal in 2 cups of boiling water for 1/2 an hour.
Add salt and onions and cook covered at HI for 5 minutes.
Stir and cook again at 70% for 10 minutes. Mash the dal to a pulp or blend in a blender. Mix in the sugar and the sambhar masala.
In another dish, mix together the mustard seeds, curry leaves, red chillies and the oil. Cook covered at HI for 3 minutes.
Add the dal mixture to this along with 2 cups of boiling water and cook covered at 70% stirring once.
Mix in the tamarind and cook covered at 30% for 5 minutes. Serve garnished with coriander leaves, accompanied with idlis or plain boiled rice.
Key Ingredients: pigeon pea, curry leaves, coriander leaves, mustard seeds, tamarind, salt, sugar, onion, red chilli, vegetable oil