Potatoes and onions are peeled and grated. Mix well and pressed so as to remove the maximum amount of liquid. Season with salt and pepper to taste. In a pan pour sunflower oil and allowed to warm. With a spoon scoop of potato mixture is placed in boiling sunflower oil and pressed with a spoon to get a flat and quite thin pancake. When the bottom browned, turning pancake and fry the other side. Serve hot with sour cream.