By William Lander, Shaun Searley and Daniel Morgenthau
This is the ideal accompaniment to a plate of ham or yesterday’s roast. Richness from the mayo, spice from the mustard and the clean acidic hit of crème fraîche work brilliantly here.
Mix all the ingredients except for the celeriac in a large bowl and put to one side.
Peel the celeriac and thinly slice using a mandoline. You may have to cut the celeriac in half or in quarters, depending on the size of the celeriac and your mandoline. Take the slices and thinly slice them into matchsticks. Celeriac can discolour quickly once cut, so quickly add to the bowl and stir to