The dough is deliberately left unleavened and thin, so the pasty was traditionally judged by how well you could still see the potato filling shining through the open top.
Kalitki are small open-topped pasties made from thin rye dough, folded up around a filling of mashed potato, barley, or rice porridge, then baked until the edges crisp. They're a signature snack of Russian Karelia, brushed with melted butter and eaten warm by hand.