Surströmming Tunnbrödsrulle

Surströmming — fermented Baltic herring — is one of the world's most pungent foods, yet its devoted Swedish following insist it is transcendent when assembled correctly: wrapped in soft tunnbröd flatbread with sour cream, finely diced onion, and mandelpotatis. The fermentation tradition dates to at least the 16th century in northern Sweden.

Serves: 4

Ingredients

• 1 can (400g / 14 oz) surströmming (fermented herring — open outdoors)
• 8 sheets mjukt tunnbröd (Swedish soft flatbread) or flour tortillas as substitute
• 300g (10 oz) mandelpotatis (almond potatoes) or small waxy potatoes, boiled and cooled
• 150ml (⅔ cup) crème fraîche or sour cream
• 1 small red onion, very finely diced
• 2 tbsp finely chopped fresh dill
• 1 tbsp finely chopped fresh chives
• Crushed white pepper

Instructions

1. Open the surströmming can outdoors or over a sink — the pressurised liquid releases strong aromas. Drain and rinse the fillets briefly under cold water.
2. Remove any remaining bones from the fillets and cut the fish into rough pieces.
3. Boil potatoes in salted water for 15-18 minutes until just tender. Drain, peel if desired, and slice into rounds.
4. Lay a sheet of tunnbröd flat. Spread 2 tbsp crème fraîche across the centre third.
5. Layer potato slices, then pieces of surströmming, then finely diced red onion on top of the crème fraîche.
6. Scatter with dill and chives and season with white pepper.
7. Roll the tunnbröd tightly around the filling. Serve immediately.

Cook's Notes: The pungency of surströmming dissipates significantly inside the roll — the crème fraîche and potato mellow it considerably. Never open the can indoors. First-timers should start with a smaller portion of fish. The season runs August to early autumn, coinciding with the traditional surströmmingsskivor (fermented herring parties) of northern Sweden.