Ingredients

Tamarind juice : 2 cups
Tomato : 1
garlic : 2 pods
curry leaves : 5
coriander leaves (finely chopped) : 2 tbsp
turmeric powder : a pinch
salt : to taste
oil : 2 tsp
mustard : 1 tsp
cumin : 1 tsp
red chilli : 1 small

For the powder :
pepper : 1 to 1.5 tbsp
cumin : 1 to 1.5 tbsp
red chilli : 1 (medium size)
Thoor dal : 1 tbsp

METHOD

Take 1 medium sized tomato, mash it and add it to the 2 cups of tamarind juice/extract.
Heat oil in a wok, and add mustard. After the mustard splutters, add cumin. Once the cumin becomes brown pour in the tamarind juice with tomatoes , and add salt, turmeric powder, mashed garlic, curry leaves, 1 red chilli split into two and rasam powder. Bring it to a boil, switch off the stove and add the coriander leaves.

You can either drink this as hot soup, or serve with white steamed rice.