Soak the daal for at least 2 hours.
Drain the water completely.
Grind it with just 2-3 tablespoons of water in a Blender or Food Processor.
Cover tightly & Let it ferment overnight or 8-10 hours.
Add salt & green chilies.
Beat the batter vigorously for 2-3 minutes. It should be light & fluffy.
Take a tiny blob of the batter & drop it in a small bowl of water to test. If the batter sinks, beat more. If it floats immediately, you are good to go.
Heat enough oil in a large wok for deep frying.
Keep a medium bowl of water on the side. Wet your hands lightly.
Take a lemon size blob of the batter in your right hand.
Then transfer it to your left wet palm.
Dip your right index finger in the water & make a hole in the middle of the blob.
Now wet your right hand & transfer the blob to your right hand.
Slide it gently into the hot oil. Repeat.
Tip: Fry the Vadas in batches. 5-6 per batch depending upon the size of the wok. Turn them a few times until the vadas are crisp & golden.
Enjoy hot dunked in Sambar & Coconut Chutney on the side.
Note: 1.During hot summers the batter may rise in just 4 to 5 hours & during winters it may take up to 16 hours or so.
Note: 2.The oil should be very hot in the beginning. To check if the oil is ready or not, drop a tiny blob of the batter into the oil. It should float immediately & fluff up. Reduce the heat to medium as soon as one batch is in the wok. For the next batch, the heat should be high again.
Note: 3.If you are in a hurry & do not want to wait until the batter ferments, then add 1/4 teaspoon of baking powder to the batter. Whisk vigorously for 5-6 minutes. Then follow the same steps as above. I personally prefer a well fermented batter because it tastes much better.