Sounds like kalakukko. From Wikipedia :

Kalakukko is a traditional food from the Finnish region of Savonia made from fish baked inside a loaf of bread. The Cornish pasty from Cornwall has the same basic idea of complete packed lunch. Kalakukko is especially popular in Kuopio, capital city of the Northern Savonia region. Kuopio is home to many kalakukko bakeries. The city also hosts an annual kalakukko baking contest.[1]

Traditionally, kalakukko is prepared with rye flour (like ruisleipä), although wheat is often added to make the dough more pliable. The filling consists of fish, pork and bacon, and is seasoned with salt (unless the pork is already salted). After being baked for several hours, traditionally in a masonry oven, kalakukko looks much like a large loaf of rye bread. If prepared correctly, bones of the fish soften and the meat and fish juices cook thoroughly inside the bread. This results in a moist filling.