This recipe for meatballs in white sauce or knigsberger klopse is actually for meatballs (klopse) prepared in the style of knigsberg. Until 1946, knigsberg was a city in east prussia (now poland) that was once part of germany. This prussian specialty is now prepared throughout germany. It is flavored with capers and lemon juice and served with potatoes and pickled beets. Note that german ground meat recipes usually are made with a combination of at least two different meats. Most often it is pork and beef, but it can include ground veal or lamb, or sometimes fish.