SERVES 4

This low-fat soup is brimming with vitamin C, iron and calcium.

2 tbsp olive oil

1 sweet onion, peeled and finely chopped

1 small potato, about 150g, peeled and diced

300g watercress, washed and thicker stalks removed

75-100g baby spinach leaves, plus

a handful to garnish

800ml vegetable or chicken stock

Sea salt and black pepper

Squeeze of lemon juice

3-4 tbsp crème fraîche, to serve (optional)

1 Heat the olive oil in a large saucepan and add the onion and potato. Sauté gently, stirring frequently, for about 10 minutes until the vegetables are soft but not brown.

2 Add the watercress and spinach, then pour in enough stock to cover the vegetables. Bring to the boil and season with salt, pepper and a squeeze of lemon juice. As soon as the spinach and watercress have wilted, remove the pan from the heat.

3 Purée the soup in two batches, using a blender. Pour into a wide bowl and leave to cool completely. Cover with clingfilm and chill for a few hours or overnight.

4 To serve, pour the soup into chilled bowls and garnish with a few baby spinach leaves. Add a small dollop of crème fraîche if you wish, and grind over some pepper.

Extracted from Gordon Ramsay¹s Healthy Appetite, published by Quadrille Publishing on May 4. Text © Gordon Ramsay 2008. Photography © Lisa Barber 2008.

Available from BooksFirst priced £17.50 (RRP £20), free p&p, on 0870 1608080; timesonline.co.uk/booksfirst

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