Seared Beef Fillet with Celeriac and Mustard and Horseradish Relish

This is a celebration of the wonderful celeriac, a root vegetable available during the colder months of the year. It is commonly used in European cooking, particularly French, and has a creamy-coloured flesh that tastes like a celery-flavoured potato. The celeriac harmonises perfectly with the Mustard and Horseradish Relish, so make the most of it when it is in season.