Soak the lentils in water for 3 hours and then cook it first using little salt.
When lentils gets cooked add the vegetables and shallot to it.
Stir well and add salt and water if needed.
Then close it and wait until it gets cooked.
When it gets cooked add coriander leaves and tamarind to it and let it boil.
Add chilly powder , sambhar powder and coriander powder to it.
Stir well and then close it and off the flame.
Heat a pan add oil in it and when its hot add mustard and yellow mustard to it.
When it splutters add dried red chilly, asafoetida powder ,curry leaves and green chilly.
Stir well and then pour this matter to the sambhar.
Then stir well and transfer to the serving dish.