Celery Root Remoulade

INGREDIENTS

• 1/4 cup mayonnaise
• 1/4 cup creme fraiche
• 2 tablespoons freshly squeezed lemon juice
• 1 teaspoon Dijon mustard
• 12 cornichons, minced (about 1/3 cup)
• 1 tablespoon finely chopped fresh flat-leaf parsley
• 1 teaspoon finely chopped fresh tarragon
• 1 teaspoon capers, rinsed and chopped
• 1/2 teaspoon coarse salt
• Freshly ground pepper
• 1 celery root (about 1 pound), peeled and julienned
• 1 head Boston lettuce, leaves separated, washed and dried