Ingredients

　　Working quickly to prevent discoloration, peel a 1-pound head of celeriac, cut into chunks, and shred in a food processor or hand-held vegetable-julienne machine. At once, toss with 1/2 teaspoon of salt and 1 1/2 tablespoons of lemon juice and let macerate 30 minutes. For the dressing, whisk 1/4 cup Dijon-type mustard in a warm mixing bowl, dribbling in 3 tablespoons boiling water followed, in dribbles, by 1/3 cup olive oil or vegetable oil and 2 tablespoons wine vinegar, to make a thick, creamy sauce. Fold into the celery root, correct seasoning, and garnish with chopped parsley. You may serve at once, or cover and let steep for an hour or longer in the refrigerator, where it will improve in flavor and tenderness.

　　Julia's Kitchen WisdomKnopf