Janssons Frestelse (Jansson's Temptation)

Sweden — first printed recipe in the 1940s; associated with the Swedish smörgåsbord tradition; the name's Jansson is disputed between multiple historical figures

A Swedish anchovy and potato gratin with layered ambition — julienned raw potatoes layered with caramelised onion and Swedish ansjovis (a spiced, salt-cured sprat, not Italian anchovies), then baked under a blanket of heavy cream until the potato is tender, the cream has absorbed into a rich, savoury sauce, and the top is golden-brown. The name's mythology involves a 19th-century Swedish opera singer caught eating fish gratin despite his professed vegetarianism. The key distinction is the Swedish ansjovis — which is sweeter, more lightly brined, and spiced with allspice and cloves — versus Italian anchovies, which would make the dish too salty and lack the spiced sweetness. The cream is added in two stages to regulate absorption.

• The anchovy-potato-cream bake parallels Basque bacalao gratin and French gratin dauphinois (no fish); anchovy as background seasoning (rather than dominant flavour) echoes the Italian 'insaporire' technique; the cream-potato structure appears in Scottish cullen skink

Served as a side dish at julbord (Christmas buffet) and smörgåsbord; also a standalone winter dinner with bread; pairs with cold light lager or akvavit; the sweetly spiced fish note is an acquired taste that rewards patience