In a bowl mix the rice and urad dal, wash till water runs clear. Soak the mix for 30 minutes.
In a pressure cooker, add the mixed rice-dal, salt, 3 cups water and cook the mix as you would cook khichri or for 2-3 whistles. Turn off the flame and allow the pressure to subside.
Turn out the cooked rice-dal into a wide bowl and bring it to room temperature.
Add in the remaining ingredients, except oil and combine it to soft dough consistency. Taste the mix and adjust the seasoning.
Divide the dough in lime sized balls.
Place the dough ball on a wet cheese cloth/ old cotton cloth, press it to flatten slightly and poke hole in the middle.
Slide the shaped vada in hot oil, one at a time and fry 4-5 vadas at a time. Fry on gentle flame till the vadas are golden brown in colour.
Serve the vadas hot with chutney of your choice.