Peel and mash the boiled potatoes keeping the crumbly in texture.
Heat two tablespoons of oil in a pan on medium heat.
Add mustard seeds and as the seeds crack add mashed potatoes, ginger paste, minced green chili, turmeric, and salt.
Stir fry for about 3 minutes over medium heat. Add cilantro mix it well. Turn of the heat.
After mixture cools off, divide the potato mix slightly bigger than a golf ball.
Make them into smooth ½ inch thick patties, rolling between slightly greased palms.
Heat oil in a frying pan on medium high heat.
The frying pan should have about 1 ½ inch of oil. To check if the oil is ready, put one drop of batter in oil. The batter should come up but not change color right away.
Dip the potato patties into the batter one at a time, making sure the patties are completely covered by the batter. Then, slowly drop them into the frying pan.
Vada will take about 4 to 5 minutes to cook.
Turn them occasionally. Fry the vada until both sides are golden-brown.