Cook the lentils in water for
about 1 hour until tender. Drain and set aside. Put
the tomatoes, tamarind pulp, asafetida, rasam powder
and salt into a pan.
Add 250ml/8 fl oz/1 cup of
water and bring to the boil, crushing everything
together. Simmer for 15 minutes. Add the cooked
lentils and remaining water and bring to the boil.
Heat the ghee and add the
remaining ingredients except the coriander. Fry
until the mustard seeds start crackling then stir
into the rasam.
Serve hot everything together.
Simmer for 15 garnished with coriander.