Pressure cook dal and tomatoes.

Mash dal to fine paste. Remove peel from boiled tomatoes and mash it well.

In a bowl, add all dry ingredients - rasam powder, salt, jaggery, turmeric powder, hing, cilantro leaves, curry leaves. Add about 1 cup of water.

Allow this mixture to boil well. Once it starts to boil, add the cooked dal and allow to boil.

Once this boils, add the tomato paste and about 2 cups of water. Allow this to cook for 8-10 minutes till it comes to a good boil.

For seasoning, melt ghee in a pan. Add mustard seeds and let them splutter. Once the mustard seeds splutter, add hing. Add the seasoning to the boiling Rasam.