First, you peel the celery root with a knife (the skin is too tough and irregular for a peeler), cut it into chunks, and then shred a celery root in a processor.

Immediately fold in a good cup of mayonnaise, enough to dress the celery root well—along with a generous dollop of Dijon mustard, a splash of vinegar (or some freshly squeezed lemon juice), salt and pepper. If you like, you can some chopped parsley for extra flavor and color.

Refrigerate for a good hour or more before serving.