The term European dumpling is often used to refer to the traditional Polish dish known as pierogi. Pierogi are small, semi-circular dumplings made from unleavened dough and filled with a variety of savory or sweet fillings. They are boiled in water and then served with melted butter, sour cream, fried onions, and other condiments. Pierogi are a popular dish in many parts of Europe, especially in Poland, where they are considered a national dish.