Bring a large pan of salted water to the boil and add a splash of the vinegar (this seasons the beetroot) followed by the beetroot. Simmer for 45 mins-1 hr, or until the beetroot can be easily pierced with a knife. Drain, leave to cool, then peel.

Meanwhile, mix the soft cheese, lemon zest, thyme and oregano together. Add the garlic, then season to taste. Cover and chill until needed. Both the beetroot and filling can be prepared up to a day in advance and chilled until needed.

Lightly oil a 450g loaf tin and line with two layers of baking parchment, leaving enough excess to allow you to cover the top. Using a mandoline or sharp knife, thinly slice the cooked beetroot into 1.5-2mm slices.

Arrange a thin layer of overlapping beetroot slices in the bottom of the tin. Spoon over a thin layer of the filling, then repeat until everything has been used, finishing with a layer of beetroot slices. Cover, then weigh down the terrine with a piece of card and a couple of cans. Chill overnight.

For the walnut brittle, line a baking tray with baking parchment and set aside. Toast the walnuts in a small, dry frying pan over a medium heat until they smell nutty. Tip out onto the tray and spread out in an even layer. Return the pan to the heat and sprinkle in the caster sugar. Cook until caramelised, swirling the pan occasionally but not stirring, until you have a deep amber caramel. Carefully pour this over the walnuts, then sprinkle with a large pinch of chilli flakes and sea salt. Leave to cool. Once cool, break the brittle into shards or pulse in a food processor for a finer texture. The walnut brittle can be made a week in advance and kept in an airtight container at room temperature.

To serve, unwrap the beetroot terrine and turn out onto a board. Remove the baking parchment and top with the walnut brittle, then slice. Serve with toast and a balsamic-dressed salad, if you like.