Chilled courgette soup

• 1 large onion
• 2 tablespoons oil
• 1 lb (450

Peel and finely chop the onion. Heat the oil in a large saucepan over low heat, add the onion and fry gently for 5 minutes to soften but not brown.

Trim and slice the courgettes and add to the saucepan. Stir in the stock and bring to the boil, then lower the heat and simmer gently, covered, for about 30 minutes, until courgettes are soft. Draw off the heat and season with salt and peppe