A whole kalakukko keeps for about a week without refrigeration, which is why loggers and farmers once carried it into the forest as a packed lunch.
Small fish like vendace or perch are layered with pork fat inside a thick rye dough, sealed into a loaf, and slow-baked for hours until the crust turns dark and the fish inside steams tender. Kuopio's market hall and bakeries sell it whole or by the slice.
Muikku (Fried Vendace)