2 lbs celery root
1 1/2 tsp salt
2 tbsp lemon juice
1 cup mayonnaise
1 tbsp Dijon mustard
1 tbsp whole grain mustard
1 tbsp lemon juice
2 tsp white wine vinegar
or Champagne vinegar if available
1/4 tsp salt
1 pinch pepper
Cut off the outer brown surface of the celery root with a serrated knife until you reach the white, creamy center. Cut the celery root into thin matchsticks with a mandoline, or grate it in a food processor fitted with the coarsest grating blade. With the food processor, press down gently as you feed the celery root through so that you get longer strands. Transfer the celery root to a large bowl.
Combine the salt and lemon juice with the celery root. Rest the mixture at room temp for about 30 minutes.
For the dressing, whisk together the mayonnaise, the 2 different mustards, the lemon juice, the vinegar, salt, and pepper in a small bowl or measuring cup.
After the celery root has rested, add just enough sauce to lightly moisten the salad. Don't feel obliged to use up all of the dressing or else the remoulade will become too saucy and soggy. Serve the salad cold or at room temp.