Rinse the rice 4 to 5 times until the water runs clear. Now add the rice to a bowl with sufficient water and soak for atleast 4 to 6 hours.
After 6 hours, drain the water. Add ¼ cup of water to the blender and add the rice into the mixer jar. I made the batter in one shot and did not divide it into batches as I went with a small quantity.
I used my Blendtec, used the batter setting, and ground the batter for 60 seconds, and in between, I added ½ cup of water. Overall I used ¾ cup of water.
Transfer the batter to a bowl, rinse the mixer jar with 2 tbsp, and add it. Add salt and mix well.
The batter is ready, and it should be in running consistency more like neer dosa. No fermentation is required. You can make the dosa right away.
Make the rice dosa.
Heat a well seasoned cast-iron pan, and when it is hot, reduce the heat to medium-low. Take a ladle full of dosa and pour the batter from outwards toward the inner side of the tawa, similar to rava dosa. You don't need to spread it like regular dosa. If there are gaps, fill them in with the batter. Few gaps are ok.
Spread some oil around the edges, cover the dosa, and cook for about a minute. The timing is approx; make sure the top side is well cooked.
When the top part is fully cooked, loosen the edges, flip the dosa, and cook for 30 to 45 seconds.
Now flip the dosa and remove it from the pan. Similarly, make the dosa with the remaining batter and serve hot with chutney or coconut milk or other sides of your choice.
Notes
You can use brown rice, hand-pound rice, or idli rice to make this dosa. You can make an instant version with rice flour.
I have mentioned the water measure I used; please adjust as required. The amount might vary as per the rice quality.