Janssons Frestelse (Jansson's Temptation)

About This Recipe

Janssons frestelse — Jansson's Temptation — is a potato casserole built around Swedish sprats (small pickled anchovy-like fish, sold specifically for this dish), layered with thinly julienned potatoes and onion, then drenched in cream and baked until the top turns deep golden and the potatoes soften into the salty, briny cream. It's one of the fixtures of the Swedish julbord, the Christmas smörgåsbord, and also shows up as a late-night snack after a party, valued for how well it survives reheating. The dish depends on using the right fish: Swedish ansjovis (which despite the name is actually cured sprat, not true anchovy) has a sweeter, milder brine than Mediterranean anchovies, and substituting the wrong product changes the dish considerably. Potatoes are cut into thin matchsticks rather than rounds so they cook through evenly and soak up the cream fully, while a layer of breadcrumbs on top crisps under the oven's heat for textural contrast. The origin of the name is genuinely uncertain — some link it to a Swedish opera singer, others to a devout religious sect member who supposedly couldn't resist it — but the dish itself has been a fixture of Swedish home cooking since at least the early 20th century.

Ingredients

Serves 6

• 1 kgpotatoes(peeled, cut into thin matchsticks)
• 2yellow onions(thinly sliced)
• 3 tbspbutter(divided)
• 100 gSwedish sprats(ansjovis, chopped, plus their brine)
• 1.5 cupsheavy cream
• 0.5 cupmilk
• 0.25 tspwhite pepper
• 0.33 cupbreadcrumbs
• 2 tbspfresh parsley(chopped, for garnish)

Instructions

1. 1

   Cook the onions

   Melt 2 tbsp butter in a pan over medium heat, cook onions until soft and golden, about 10 minutes.

2. 2

   Layer the gratin

   Butter a baking dish. Layer a third of the potatoes, then half the onions and sprats. Repeat, finishing with a potato layer on top.

   Cut potatoes into thin, even matchsticks — thick pieces won't cook through in the baking time.

3. 3

   Add the cream

   Whisk cream, milk, sprat brine and white pepper together and pour evenly over the layered potatoes.

4. 4

   Bake covered

   Cover with foil and bake at 200°C (400°F) for 30 minutes.

5. 5

   Finish uncovered

   Remove foil, scatter breadcrumbs and dot with remaining butter. Bake uncovered for 15-20 more minutes until deep golden and bubbling.

6. 6

   Rest and serve

   Rest 10 minutes, scatter with parsley, and serve hot as a main or Christmas side.

Variations

• •

  Add a layer of grated cheese under the breadcrumbs for a richer, more indulgent version.

• •

  Make individual portions in ramekins for a more elegant holiday presentation.

• •

  Reduce the fish for a milder version, though purists consider the full amount essential.

Storage

Refrigerate up to 4 days; it's traditionally eaten reheated the next day as a late-night snack after a party. Reheat covered in a 160°C oven until warmed through.

Frequently Asked Questions