In a mixer jar take peeled and cubed potatoes and onion.
Grind to a smooth batter.
Alternately you can grate them in a fine grater.
Add all the other ingredients except oil and mix well.
The batter needs to be pourable.
Heat a non stick tawa and place spoon full of batter on it.
Drizzle oil along the sides and cook them on both sides until golden.
Serve with sour cream.