Mysore Bonda is prepared either with maida or ulundu i.e. urad dal. You do not worry about making this bonda with ulund because when you are grinding for idli or dosa, bit extra urid can be put and grind it. But the batter should be like the medu vada batter and should not go extra water in it.
I used to make this bonda without adding any other stuff like the ingredients we add for the mysore bonda. Here I would like to give you a tip - in case the batter has extra water in it, just add bit of rice flour and rava and keep in fridge, which will absorb the extra water in it.
coming back to the recipe, I made today the mysore bonda with urid dal. As I said, while grinding for idli, I had taken out some urid batter and kept aside. I used that only for making the bonda.
It is an easy snack item which can be served with chutney or sambar. My children would be happy to serve it along with sauce.