Ingredients to serve 4

4-5 medium beetroot, cleaned and trimmed, their whiskers left on
1 tablespoon olive oil
1 small red or white onion, finely chopped
1 small garlic clove, peeled and finely chopped
Sea salt and black pepper
1.2 litres/2 pints hot chicken stock or water
1 thick slice stale, good black rye bread, crust removed
A little good live yoghurt to finish
1 teaspoon finely chopped tarragon or dill

The sweet earthiness of beetroot with its brilliant hue is such a great thing in the dark night of the soul-food winter. Roast the beetroot ahead and the soup takes no time to make.

Preheat the oven to 200C/gas mark 6. Wrap each beetroot separately and tightly in a piece of foil, except for the one you are going to grate in raw at the end. Roast in the oven for about an hour until cooked. To check, unwrap and pierce with a skewer through to the centre; it should meet with little resistance. Peel the beetroot as soon as they are not too hot to handle and cut them into chunks.

Meanwhile, heat the olive oil in a large, heavy-bottomed pan and add the onion and garlic. Season with a little salt and sauté over a medium heat until softened. Add the roasted beetroot chunks, followed by the hot stock or water. Bring to a simmer and cook gently for no more than five minutes without a lid. You want this part of the cooking process over as quickly as possible so that the beetroot retains its vibrant colour.

Remove from the heat, season with black pepper and add the rye bread. Using a blender, purée the soup in batches. The texture should be thick, yet not too thick. If in doubt, add another ladle of hot stock to thin the soup down a bit. Check the seasoning.

Grate the remaining beetroot coarsely. Pour the soup into warm soup plates and spoon the grated beetroot into the middle. Top with a spoonful of yoghurt and a sprinkle of chopped tarragon or dill.

From 'Supper For A Song' by Tamasin Day-Lewis (Quadrille, £20).

Sommelier's choice

Private Selection Sauvignon Blanc, USA

This wine is fresh on the palate, with rich flavours of lime, grapefruit and some melon that will nicely complement the beetroot.

Tesco, £6.99,