Good smoked trout needs very little from you. The fish arrives already transformed by smoke and salt, its flesh silky and rich with a gentle sweetness that cold-smoked salmon cannot match. Your job is to find a fishmonger or farmer who sources responsibly, someone who can tell you where the fish swam and how it was smoked.

This tartine comes together in minutes, but the pleasure it delivers belongs to a longer tradition. In France, an open-faced sandwich like this might appear at the start of a meal or as a light lunch with a glass of cold white wine. The dark bread provides a sturdy base and a touch of sweetness. The horseradish cream brings heat without shouting. And the watercress, that peppery green that grows in cold streams, ties everything back to the water.

Every meal is a meaningful choice. When you buy trout from someone who raises fish sustainably, you are voting for clean rivers and careful stewardship. The tartine tastes better for knowing this.