Potato Pancakes Placki Ziemniaczane

Peel the potatoes and onion, and grate both finely. Remove the juice. Mix in the egg, lightly beaten, and season well. Add flour and stir until the mixture holds its shape. Pour enough oil into a large frying pan to cover the bottom of it. When it is hot, drop spoonfuls of the potato mixture, flatten them so they are very thin. Brown on both sides. Serve right from the pan with sour cream.