Place potatoes in a medium sized saucepan and cover with water; salt lightly. Bring to a boil over medium heat and cook until fork-tender; drain. Place potatoes in a large bowl and mash; then allow to cool for 5-10 minutes. Stir onions, drained sauerkraut, egg, salt, pepper, caraway, flour, and breadcrumbs into potatoes, forming a thick mixture. Pour some flour in a small bowl; do likewise to some bread crumbs. Beat 2 eggs in a small bowl also, set aside (Add more egg later if necessary). Heat deep fryer or oil (several inches deep in a frying skillet) to a temperature of 350 degrees. Take heaping tablespoonfuls of the potato mixture and roll in flour. Then coat with egg, then roll in bread crumbs. Do the same with several others. Fry balls (which should be the size of large meatballs) in small batches for 2-4 minutes or until golden brown. Drain on paper toweling, and serve hot. Makes 25 extra-large balls, or enough to serve about 6 people.