Jansson’s Temptation: The Ultimate Swedish Midnight Gratin

🌍 Cuisine: Swedish
🏷️ Category: Main Course
⏱️ Prep: 25 minutes
🍳 Cook: 50-60 minutes
👥 Serves: 6 servings

📝 About This Recipe

A cornerstone of the Swedish 'Julbord' or Christmas smorgasbord, Jansson’s Temptation is a luxurious, creamy potato gratin that balances the richness of heavy cream with the salty, umami-rich punch of Swedish pickled sprats. Named after a 19th-century opera singer with a legendary appetite, this dish transforms humble pantry staples into a sophisticated masterpiece of comfort food. The secret lies in the contrast between the tender, matchstick-cut potatoes and the golden, buttery breadcrumb crust that shimmers with savory depth.

🥗 Ingredients

The Foundation

  • 2.2 lbs Starchy Potatoes (such as King Edward or Russet, peeled)
  • 2 large Yellow Onions (thinly sliced into half-moons)
  • 3 tablespoons Unsalted Butter (for sautéing the onions)

The Savory Soul

  • 1 tin Swedish Anchovy Fillets (approx. 3.5-4 oz; these are actually spiced sprats (Ansjovis))
  • 2 tablespoons Anchovy Brine (reserved from the tin)

The Liquid Gold

  • 1.5 cups Heavy Cream (at least 36% fat content)
  • 1/2 cup Whole Milk (to balance the richness)
  • 1/2 teaspoon White Pepper (freshly ground)
  • to taste Salt (be cautious as the fish is salty)

The Topping

  • 3 tablespoons Plain Breadcrumbs (fine texture)
  • 2 tablespoons Cold Butter (cut into small cubes)

👨‍🍳 Instructions

  1. 1

    Preheat your oven to 400°F (200°C) and generously grease a 9x13 inch baking dish with butter.

  2. 2

    Peel the potatoes and cut them into thin matchsticks (julienne), roughly 1/8 inch thick. Do not soak them in water, as the starch is needed to thicken the cream sauce.

  3. 3

    Melt 3 tablespoons of butter in a large skillet over medium-low heat. Add the sliced onions and sauté slowly until they are soft and translucent, but not browned, about 8-10 minutes.

  4. 4

    Drain the Swedish anchovies, making sure to reserve at least 2 tablespoons of the spiced liquid from the tin.

  5. 5

    Begin layering the dish: Place one-third of the julienned potatoes in the bottom of the prepared baking dish.

  6. 6

    Top the first potato layer with half of the sautéed onions and half of the anchovy fillets, spacing the fish evenly.

  7. 7

    Add another third of the potatoes, followed by the remaining onions and the remaining anchovy fillets.

  8. 8

    Finish with a final layer of potatoes on top, smoothing them out to create an even surface.

  9. 9

    In a small bowl, whisk together the heavy cream, milk, white pepper, and the reserved anchovy brine. Pour this mixture evenly over the casserole.

  10. 10

    Sprinkle the breadcrumbs evenly across the top and dot with the small cubes of cold butter.

  11. 11

    Bake in the center of the oven for 45-60 minutes. If the top begins to brown too quickly, tent it loosely with foil.

  12. 12

    The dish is done when the potatoes are tender when pierced with a knife and the liquid has thickened into a bubbling, creamy sauce.

  13. 13

    Remove from the oven and let the gratin rest for 10 minutes before serving; this allows the sauce to set perfectly.

💡 Chef's Tips

Always use Swedish 'Ansjovis' (pickled sprats) rather than Mediterranean salt-cured anchovies, as the flavor profile is sweet and spiced rather than just salty. Cut the potatoes by hand rather than using a food processor to ensure the pieces are uniform and don't turn into a mushy texture. Use high-fat heavy cream; low-fat alternatives may split due to the acidity of the anchovy brine. If the dish looks too dry halfway through baking, splash an extra 1/4 cup of warm milk around the edges. For the best flavor, make the dish a few hours ahead and reheat it; the flavors deepen significantly over time.

🍽️ Serving Suggestions

Serve as part of a traditional Swedish Smörgåsbord alongside pickled herring and crispbread. Pair with a chilled glass of Aquavit or a crisp, dry pilsner to cut through the richness. Accompany with a side of tart lingonberry jam for a classic sweet-and-savory Swedish contrast. Serve as a late-night 'vickning' (midnight snack) after a festive party with some simple rye bread. Pairs beautifully with a simple green salad dressed in a sharp lemon vinaigrette.