Janssons Frestelse (Jansson's Temptation)

Ingredients

Equipment Needed

• •Mandoline slicer or sharp knife
• •9x13-inch baking dish or 3-quart oval gratin dish
• •Large skillet
• •Aluminum foil

Instructions

1. 1

   Slice the potatoes

   Using a mandoline or sharp knife, slice the peeled potatoes into rounds about 1/8-inch thick. Consistent thickness matters here. Too thick and they won't cook through; too thin and they'll dissolve into mush. Place slices in cold water to prevent browning while you prepare the remaining ingredients.

   Yukon Golds hold their shape better than russets while still absorbing cream beautifully. Don't substitute.
2. 2

   Caramelize the onions

   Melt 2 tablespoons butter in a large skillet over medium heat. Add the sliced onions and cook slowly, stirring occasionally, until soft and golden but not browned, about 12-15 minutes. You want sweetness, not char. The onions should look translucent and smell faintly caramelized. Season lightly with a pinch of salt. Remove from heat and set aside.

3. 3

   Prepare the anchovies

   Drain the Swedish anchovies over a bowl, reserving the liquid. This brine is liquid gold. Roughly chop the anchovy fillets into smaller pieces, about 1/2-inch long. They'll distribute more evenly through the layers this way.

4. 4

   Prepare the baking dish

   Preheat your oven to 400°F (200°C). Generously butter a 9x13-inch baking dish or oval gratin dish with 1 tablespoon of the remaining butter. The butter prevents sticking and contributes to those irresistible crispy edges everyone fights over.

5. 5

   Layer the gratin

   Drain the potato slices and pat them completely dry with kitchen towels. Wet potatoes steam rather than roast. Arrange one-third of the potatoes in overlapping rows across the bottom of the dish. Season with white pepper (no salt yet, the anchovies provide plenty). Scatter half the onions over the potatoes, then half the chopped anchovies. Repeat with another third of the potatoes, the remaining onions, and remaining anchovies. Finish with a final layer of potatoes arranged in neat, overlapping rows. This top layer is your presentation.

   Take your time with the top layer. Overlapping shingles of potato create the most beautiful finished appearance.
6. 6

   Add the cream mixture

   Combine the heavy cream, milk, and reserved anchovy liquid in a measuring cup. Pour this mixture slowly over the layered potatoes, letting it seep down through the layers. The liquid should come about three-quarters up the sides of the potatoes but not cover them completely. The exposed top layer will crisp.

7. 7

   Top and bake

   Sprinkle the breadcrumbs evenly over the top and dot with the remaining tablespoon of butter, cut into small pieces. Cover the dish tightly with aluminum foil and bake for 30 minutes. The covered stage allows the potatoes to steam and soften.

8. 8

   Finish uncovered

   Remove the foil and continue baking for 25-30 minutes more, until the top turns deep golden brown, the cream bubbles vigorously around the edges, and a knife inserted into the center meets no resistance. The gratin should be fragrant, almost sweet-smelling from the anchovies and caramelized cream.

   If the top browns too quickly before the potatoes are tender, tent loosely with foil for the final 10 minutes.
9. 9

   Rest and serve

   Let the gratin rest for 10 minutes before serving. This allows the cream to be absorbed and makes portioning easier. Garnish with fresh dill if desired. Serve directly from the baking dish, family-style, as is traditional. Each portion should include some of those crispy edges.

Chef Tips

• •Swedish anchovies (ansjovis) are essential. They're sweet-cured sprats, nothing like Mediterranean anchovies. Find them at IKEA, specialty grocers, or online Scandinavian food shops. Abba and Grebbestad are reliable brands.
• •The dish tastes even better the second day. Reheat covered at 325°F until warmed through, then uncover briefly to re-crisp the top.
• •For a lighter version, substitute half-and-half for some of the cream. The dish will be less rich but still satisfying.
• •Pair with aquavit for a proper Swedish Christmas experience, or a crisp, dry Riesling that can stand up to the richness.
• •Leftover gratin makes an excellent breakfast. Reheat a portion in a skillet and top with a fried egg.

Advance Preparation

• •The gratin can be fully assembled, covered tightly, and refrigerated up to 24 hours before baking. Add 10-15 minutes to the covered baking time since it will start cold.
• •Onions can be caramelized up to 3 days ahead and refrigerated.
• •Potatoes can be sliced and held in cold water for up to 4 hours. Drain and dry thoroughly before layering.
• •Baked gratin keeps refrigerated for 3 days. Reheat covered at 325°F for 20-25 minutes, then uncovered for 5 minutes to crisp.

Frequently Asked Questions

Nutrition Information

1 serving (about 365g)