Never has rotten fish smelled so bad but tasted so good.
By NORTH Festival
Small Baltic herring are caught in the spring, salted and left to ferment at leisure before being stuffed in a tin about a month before it hits the tables and shops. The fermentation process continues in the tin; ‘souring’ as the Swedes refer to it, and results in a bulging tin of fermented herring or surströmming. The aroma is pungent, and the taste is rounded yet piquant with a distinct acidity.
When:
The end of August is popular, and there is a special surströmming festival in Alfta, Hälsingland in the north of Sweden. But surströmming enthusiasts prefer to savour the previous year’s vintage for tenderness and a fully mature flavour.
Where:
Outdoors is best. Always. 
Who:
Traditionalist Swedes, food lovers and adventurous tourists.
How to do it like a local:
As the tin is pressurised, open the surströmming in a basin of water. Wash it, gut it, and wrap it in buttered tunnbröd, a type of sweetened flat bread, with slices of almond potatoes and diced onion. Accompany with beer, schnapps and lots of friends.
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