Grate potatoes and onion.
Transfer to colander and squeeze mixture to press out as much liquid as possible.
In a large bowl, mix potatoes, parsley, egg, salt, pepper, flour and baking powder.
Heat oil in a deep, heavy skillet. For each pancake, drop about 2 tablespoons of potato mixture into pan. Flatten with back of spoon so each pancake is about 2 1/2 to 3 inches in diameter. Fry over medium heat for about 4 to 5 minutes on each side, or until golden brown and crisp. Turn carefully with 2 spatulas so oil does not splatter.
Drain on paper towels.
Stir potato mixture before frying each new batch. If all the oil is absorbed, add a little more to the pan.
Serve hot with applesauce, or sour cream, or sugar.