2/3 cup thick, creamy coconut milk 
1 teaspoon oil
½ teaspoon cumin seeds/jeera
2 green chopped chillies
1 sprig curry leaves/patta
1 tablespoon finely chopped coriander leaves/kuthmir
1 lime or less
Salt

Preparation:

See how to make Coconut Milk.
Add 3 cups water to the coconut milk (less if it is thin)
Fry the jeera in 1 teaspoon oil. Upon spluttering, add chopped green chillies, and curry patta.
Add the coconut milk. Mix well.
Add coriander, lime juice and salt as per taste.

Serve cold.