Instructions Make sure you read the cooking notes before you start. Step 1 – Peel the celery root and julienne/grate it into 1/8-inch thin long strips similar to matchsticks. Place sticks in a bowl and sprinkle with lemon juice as you grate so the celery root doesn’t turn brown. Step 2 – In a large bowl, combine the mayonnaise, Dijon mustard, diced cornichons, salt and pepper (and optional: 1 tbsp capers). Whisk with a fork to combine. Step 3 – Add the celery root and toss until evenly combined.Cover bowl with plastic film and chill for at least 2 hours before enjoying. The Celery Root Remoulade gets better as it sits, as it allows the celery root to soften and absorb flavours.