Soak ½ cup urad dal and ½ cup raw rice together for 2 hours.
Rinse it well, transfer to mixer jar, add water little by little and grind.
Grind to a thick smooth batter. Do not add more water, the batter should be thick.
Transfer the batter to a mixing bowl add required salt along with little water to thin the batter if needed. The batter should be thick at the same time in flowing consistency. Set aside.
To a pan heat 2 teaspoon oil - add ½ teaspoon mustard seeds let it splutter.
Add 1 tablespoon torn curry leaves along with 1 long green chili chopped finely give a quick saute.
Add ¼ cup finely chopped onion along with salt then saute until it turns transparent.
Add 2 tablespoon grated coconut and give a quick saute and switch off.
Add salt and 2 teaspoon water to the batter to adjust the consistency.
Add prepared tempering to the batter.
Mix it well and set aside.
Heat oil - check by dropping a pinch of the batter if it rises immediately then oil is ready. When the oil gets heated up pinch the batter, wipe excess at the sides and carefully drop it into the preheated oil.
Turn over to other side and fry till golden brown.
Drain excess oil and remove.
Repeat to finish the batter.