Wash and soak both the dals at least for 15 minutes.
Add sliced onions, diced tomatoes, green chillies, cloves of garlic and turmeric powder to the dal and pressure cook until soft
Mash the dal mixture and add tamarind and salt to it.
Add required amount of water and boil it once more for 2 minutes
Heat oil in a pan splutter in the mustard, red chilly,cumin, urad, curry leaves, hing and sambhar powder.
Add this mixture to the dal, garnish with coriander leaves and serve