【How-to】What is surstrommings fileer - Howto.org

Surströmming is made from Baltic sea herring, which is fermented in a weak brine for at least six months. It’s lightly salted in the can to prevent it from rotting. Those brave enough to try often eat small pieces in a flatbread wrap along with waxy potatoes, sour cream, red onion, chives and dill.