Ruby-red and intensely flavoured, this soup looks stunning swirled with sour cream. Serve as a starter or light lunch with slices of rye bread.
*If using raw beetroot, scrub them under running water, cover with plenty of cold water, add salt, and cook for at least 2½ hours (or 1 hour in a pressure cooker). Alternatively, bake small beetroot in a baking tin with a little water for 2 hours at 180°C (gas 4). *You can buy vacuum-packed cooked beetroot readily from the supermarket salad selection. Don't use the type preserved in vinegar.