Smoked Trout Salad with Herb & Horseradish Dressing

Make Ahead Tip: Cover and refrigerate the dressing (Step 1) for up to 1 week.

Crème fraîche is a tangy, thick, rich cultured cream commonly used in French cooking. Find it in the dairy section of large supermarkets, usually near other specialty cheeses. Sour cream can be used as a substitute, or you can make your own lower-fat version by combining equal portions of reduced-fat sour cream and nonfat plain yogurt.

Mâche (“mosh”), also known as lamb's lettuce or corn salad, is a tangy green that resembles watercress. Popular in Europe, it is enjoyed in the first salads of spring. Look for it in specialty stores, large supermarkets and farmers' markets.