Tarteletter med Fisk i Sennepssauce

There is a particular kind of Danish dish that lives in the brown-and-cream end of the kitchen: stuvninger, the family of creamed sauces that carry whatever the season has given you. Sennepssauce is one of the oldest. Sharp, smooth, the bite of mustard cutting through butter and milk, built to make modest fish feel like a proper meal. In winter, when the cod is firm and cold-water sweet and the herb garden has gone quiet, this is the sauce the Danish home cook reaches for.

Tarteletter are what we do when we want the same dish to feel like an occasion. The crisp puff pastry shells, hollow and golden, turn a humble braise or stew into something you serve to people who matter. The most famous version is hons i asparges, chicken and white asparagus in a pale cream sauce, the dish you eat at confirmations and silver weddings. The fish version is quieter. It's what you make on a Tuesday in February, when you want something warm and a little bit special without leaving the house.

What matters most is the temperature of the poaching liquid and the moment you add the mustard. The cod wants water that barely trembles, never bubbles. The mustard wants to go in off the heat, so its sharpness survives. Get those two things right and the rest follows. I'll walk you through every step so you're never guessing.