To a blender jar, add all ingredients mentioned to grind & grind to a coarse paste.
Soak 2-inch slice fresh tamarind in ½ cup lukewarm water & let soak for 5 minutes. After that squeeze the tamarind in water to extract the juice, strain the juice & discard the skin.
To a hot clay pan or saucepan, add oil.
Add mustard seeds, let splutter.
Add chana dal & urad dal, saute till they turn golden in color.
Add dried red chilies & curry leaves.
Add the ground paste, combine well & cook for a minute.
Rinse the blender jar with ½ cup water & add that. Cook for a few minutes till the raw smell goes away.
Add salt & asafoetida, combine well.
Add tamarind extract, cook for 2 minutes.
Add chopped beetroot & cook covered till the beetroot turns soft.
Add 1 cup water to thin down the gravy & cook for a few minutes, let rasam come to a slight boil.
Take the pan off the heat, enjoy as soup or pour over rice & enjoy.
Recipe by Cooking with Thas - Smart Cooking, Smart Living at https://thasneen.com/cooking/beetroot-rasam-south-indian-recipe/