For bhallas=first rinse all the lentils together and soak for at least 6 hours.now blend by adding little portions of them.make a smooth batter

Now transfer it in a large bowl and just whisk by hand for 10 to 15 minutes bcuz I don't recommend to add baking soda to make fluffy bhallas.just whisk and when it looks fluffy smooth batter rest it for 10 minutes

Now make oil hot in another pan and start putting small balls of batter with hand or ice cream scoop.make a small bhallas.let it fry at medium flame.

Let them cool down and put them in hot water for 10 minutes.put all the ingredients in curd and whisk well until it smooth.add bhallas to curd and enjoy with tamarind sauce