Soak urad dal for 6 to 8 hours.
Grind it to a fine smooth paste.
The consistency of the batter should be thick, as thick as we have it for vada batter.
Add only if it needed.
The batter should be like that of vada.
Thick and easily able to drop it.
Blend green chillis in a blender to make coarse paste.
Add the green chilli paste(if adding), salt to it and mix it well.
Place a plastic sheet under the sun.
Take small portion of the batter into the hand.
Slowly drop small pebble size portion of it on the sheet.
So that we can get small vadiyalu, we can drop as small as we want them to be.
Or if we want them in bigger size use a spoon and place them on the sheet.
Dry them completely for one or two days depends on the sunshine.
Do not let little moisture too left in the vadiyalu, otherwise it will spoil the item.
Once they are dried completely keep them in an air tight container. They can stored for one full year.