Add salt, cumin. Also, add the onions and other ingredients mentioned if you need them.
Check for the consistency. If it is thin, the punugulu will absorb a lot of oil.
In that case, add some maida to correct the consistency.
Take oil for deep frying in a thick bottomed Kadai.
Drop small dumplings with three fingers into the hot oil.
Fry till golden brown and transfer to the kitchen tissue to absorb excess oil.
Notes
* The dosa batter and idli batter should be thick. Adding more maida to make it thick would give the required taste and texture. So make sure the batter itself is thick. I generally grind both the batters thick so that it can be made thin if needed.** The punugulu with this batter will be crisp outside and soft inside.*** The ravva in the idly batter will enhance the texture of the punugulu and gives the crispness to them.