Boil the beans in pressure cooker with salt and turmeric and keep aside.
Mix the Channa dal and sambhar dal, red chilli and soak in water for about 4-5 hours add about 4 cups of water to soak.
Grind the soaked mixture in a mixie so that it becomes a paste.
:- Be careful not to grind it too much into a paste. Do not leave it too coarse either. We need a paste like consistency that is not too fine