1. The most important part of making the recipe is ensuring that you don't add too much water while grinding the dal. Just add very little water as much as is needed to smoothly grind.
2. Also aerate your batter by beating it well. This ensures that you get fluffy and soft vadas.
3. While air frying, you can also put the vada batter in the freezer for about 10 minutes so that it holds its shape better.
4. Some people steam the vadas in idli batter for about 5 minutes. Then they air fry the vadas at high temp for 8 minutes at 200C to brown and crisp up the outside.
5. To make a nice donut shape you can use donut mould.