Vengar rasam / Onion rasam / Indian hot and sour soup

Rasam is indian hot and sour soup goes well with hot rice. Its made of tamarind / tomato / lemon juice.
In south india rasam is being used as a medicine for fever (paati vaithiyam). Add hot rasam to smashed cooked rice, mix well and drink this semi solid at bearable warmth. This secretes enormous sweat and so the body loses the excess heat.

This version of rasam i am posting is very simple. 1-2-3 --> Squeeze-Grind-Heat

Method

To squeeze
1. Tamarind pulp - 1 lemon size ball
2. Tomato - 1

Soak the tamarind in one cup of water, extract the juice and discard the husk. Cut the tomato into 2 halfs and squeeze it in the tamarind extract.

To Grind
1. Cumin seeds / Jeera - 2 tbs
2. Garlic cloves - 3 nos (dont remove the skin)
3. Red chili (big) - 1 no
4. Pepper corns - 1 tbs
5. Big brown onion - 1 (roughly chopped) or small onions - 10 nos

Grind (coarsely) everything except onion in 1/2 cup of water. Add onion and grind for 5 sec.

To Heat
1. Turmeric powder - pinch
2. Hing / Asafoetida - pinch
3. Salt to taste
4. One handful of cilantro - washed and chopped

Mix everything from step 1 , 2 and 3 together and heat in medium flame. Do not stir the mix while heating. Slowly bubbles get formed on the top of rasam (as shown in the fig above). At this stage remove flame. Serve hot.