10g of fresh horseradish, peeled and finely grated
200g of créme fraiche
50ml of double cream
10g of Chardonnay vinegar
sea salt
freshly ground black pepper
Method
1
To make the horseradish crème fraiche, mix all the ingredients together and leave in the fridge for at least 1 hour to infuse. This will make more than you need for these sandwiches, but it will keep for a few days
2
For the pickled beetroot, bring the water, vinegar and sugar to the boil. Meanwhile, toast the spices in a dry frying pan for a few minutes until aromatic, then add to the liquor
3
Place the sliced beetroot into a heatproof container and pour the boiling pickling liquor over it through a fine sieve. Set aside to cool. This step can be prepared a few days in advance; keep the beetroot in a covered jar or bowl in the fridge
4
To serve, cut the buns in half and spread with the butter and around 60g of the horseradish crème fraiche. Divide the drained beetroot and sliced beef between the two sandwiches and season with salt and pepper. Top with a big pinch of watercress and a generous grating of fresh horseradish, then sandwich together and serve