The dough is stretched so thin in the center that it fries into a pale, tender 'window' ringed by a puffier golden edge — bakers judge quality by how wide that window is.
A rich yeasted dough enriched with egg and a splash of schnapps is rolled and stretched thin, then deep-fried until it puffs at the edges and stays pale in the middle. Salzburg's farmers markets and village fairs sell them dusted with sugar, often filled with apricot jam.