A runza (also called a bierock, fleischkuche, or Kraut Pirok) is a yeast dough bread pocket with a filling consisting of beef, pork, cabbage or sauerkraut, onions, and seasonings. They are baked in various shapes such as a half-moon, rectangle, round (bun), square, or triangle. The Runza sandwich originated in Russia during the 1800s and spread to Germany before appearing in the United States.