Mix together the rice flour, salt, coconut milk and water and make a batter of liquidity consistency, just like buttermilk. Set aside for 5-10 minutes.
Grease a non-stick tawa / griddle with very little oil and wipe clean with a kitchen towel. Pour 2-3 ladles of the prepared batter and swirl around to form a circle.
Remove excess batter if any. (There is no need to drizzle oil over it). Cover and let it cook on a low flame for a minute. Fold it in half and then into a rectangular shape.
Make similar dosa in the same method by just wiping the tawa with the greased kitchen towel. Serve with any non-veg gravy, sambar or chutney.