Heat oil in a deep bottomed vessel. Add the crushed garlic, dry red chilies, mustard seeds, cumin seeds, and coriander leaves. Saute for a minute.
Next, add in the water and salt mix well.
Next, add the turmeric powder and tamarind paste and mix well.
Bring it to a boil. Boil it for about 10 minutes.
While the mixture is boiling, prepare the rasam masala.
Blend all the ingredients into a rough paste.
Add in the prepared rasam masala. Mix well.
Boil for another 2-3 minutes.
Garnish with fresh coriander leaves.
Serve hot with rice.