Mix together 1 cup mayonnaise, homemade or store-bought, 2 ½ tbsp Dijon mustard, 1 tsp salt, 2 tbsp lemon juice and a pinch of black pepper. Set aside

Peel a small celery root (around 1kg) and grate coarsely using a food processor.

Add the mayonnaise sauce to the celery root, and adjust with additional salt, pepper, mustard and lemon juice. If too thick, thin out with a little milk or yoghurt.