On the third Thursday in August Sweden celebrate the premiere of the surströmming season.
Surströmming smells very strong and the taste is salty. One way to eat sour strömming is in a so-called clamp (surströmmingsklämma).
A sandwich is made from two equal-sized buttered pieces of hard flatbread with sliced or mashed almond potatoes that have been boiled with the skin on and finely divided surströmming in between, which are "squeezed together" into a kind of large double sandwich that is eaten with the hands.
Surströmmingsklämma can also be made from soft flat bread, also sometimes called a "stut", where the ingredients are rolled up in the bread. Other accessories that have become common in recent times, especially in the southern parts of Sweden, are raw or butter-fried yellow onion or raw red onion, butter, sour cream and sometimes tomato and dill can also be found.
Recipe from Polarbröd (Swedish)
www.polarbrod.se/recept/sasong-for-surstromming
You find Röda Ulven Surströmmingsfileer and both kind of flat breads from Polarbröd in the shop.