This Saar is done from the thick liquid / saar obtained from draining the Black Chana after being pressure cooked. Pressure cook black chana (soaked overnight or at least 8 hrs) with just required amount of water in pressure cooker to 4-5 whistles. When the pressure drops open the lid add another 2 cups of water and bring the whole thing to a good boil. Leave it aside for a few hours. Say around 5-6 hours. This thickens the liquid in which the chanas were cooked and you get good thick chana saar for making of Chane Tomato Saar.
Soak a marble sized tamarind in half cup of hot water and keep aside. When cool squeze well to get a thick tamarind pulp.
Pour 3-4 cups of Chane Saar obtained from cooking the chanas into a vessel. Add 2 finely chopped tomatoes, tamarind pulp, salt to taste, a lemon sized piece of jaggery (Optional), ½ cup of finely chopped coriander leaves and bring to a boil.
For tempering: Add 2 tblsp of oil in a small pan, when hot add a tsp of jeera, then ½ tsp of sasam (rai) when it splutters, add 2 red chillies broken into two, 7-8 curry leaves, 1 tsp of hing powder and finally 2 tblsp of sambar powder (I used the one available in Stores) and fry well in the oil a bit. Pour it over the boiling saar.
Bring the saar to a good boil after adding in the seasoning, lower heat and simmer for a good 10-15 minutes. Add water if necessary to bring to a saar consistency if too thick. Remove from fire, garnish with on top again with a handful of coriander leaves.
Serve hot with Rice. You can serve it as an appitizer too, tastes very good.