Discard the water.Add the soaked moong dal along with hing, green chilli, ginger and salt to the blender.
Grind it into a thick batter with adding ¼ Cup of water in 2 tablespoon increments.
Heat the griddle or tawa at a medium high heat.
Using a ladle, spread on a hot tawa. Add a few drops of oil. Flip and cook the other side.
Serve with chutneys or podis.
Notes
While grinding, add the water two tablespoons until you get a thick, foamy, spreadable consistency of the Pesarattu batter. The consistency is the same as regular dosa batter.
Make sure the tawa is hot before you start spreading the batter on it.
You can add chopped onions, coriander, and curry leaves to the batter or as a topping on the dosa, too.