Grind 1/2 cup quick cooking oats in a mixer or grinder to a fine flour.
Take this flour in a mixing bowl. Then add 1/4 cup rice flour and 1/4 cup semolina.
Add 1/2 cup fresh curd. You can also use sour curd. If using sour curd, then add 1/4 cup and add more water to get the right consistency. You can also add 1/4 cup fresh curd for a less sour taste.
Add 1 cup water. Stir and mix to a smooth consistency without any lumps.
Add 1/4 cup finely chopped onion, 1 tsp finely chopped ginger, 1 tsp finely chopped green chilies, 1 to 1.5 tbsp chopped coriander leaves and 7 to 8 curry leaves, finely chopped.
Stir very well again and then add 1/2 tsp cumin seeds, 1/4 tsp black pepper, crushed in a mortar-pestle and salt as required. You can also add 1 to 2 tbsp grated coconut.
Stir again and keep aside for 10 minutes.
Then check the consistency and add 1/4 cup water. Add water as required. You can add overall upto to 1.5 cups water.
Curd used was homemade and hence not very thick. If using thick curd you may need to add some more water.
The consistency should be thin and flowing like rava dosa batter.
On a medium flame heat a cast iron pan or a non-stick pan. Drizzle ½ tsp. of oil and spread it with the spoon. Before adding the oil, if using a cast iron pan, sprinkle some water to check the temperature of the pan. If the water droplets sizzle and evaporate, then the pan is ready to make dosas. Avoid doing this method on a non-stick pan as adding water on a hot non-stick pan, will affect the non-stick coating.
Stir the batter in the pan/bowl and take a ladle full of batter and pour it from the circumference to the center. Do not spread the batter with the back of the ladle like the way we do for regular dosas. Fill the small or large gaps with a bit more of the batter.
