Ingredients
2 tablespoons mayonnaise
4 teaspoons Dijon mustard
2 teaspoons fresh lemon juice
2 teaspoons chopped capers
1 teaspoon prepared horseradish
Coarse salt and ground pepper
Reserved roast beef from Roast Beef and Celery Root with Watercress Salad
8 slices country-style bread
Preparation
In a medium bowl, combine mayonnaise, mustard, lemon juice, capers, and horseradish; season with salt and pepper. Grate reserved celery root into dressing and stir to combine. Spread mixture on 4 slices country-style bread. Divide reserved watercress and roast beef among slices, then top with 4 more bread slices. (To store, refrigerate, wrapped in plastic, up to 1 day.)
