Best made an hour or two before serving.

SERVES

Four

INGREDIENTS

2 bunches of watercress (200g)
20g unsalted butter
80g white onion (¼ large one), peeled and finely chopped
¼ garlic clove, peeled and finely chopped
100g spinach, washed and picked
400ml boiling water
400g ice, crushed
4 tbsp crème fraîche, to serve (optional)

METHOD

Taste the watercress for pepperiness and, accordingly, cut off some or most of the stalks. Set aside a few sprigs for serving.

Melt the butter in a very wide saucepan over a low heat. Add the onion and garlic and sweat for about eight minutes until softened and translucent. Turn up the heat to high, add the watercress and spinach and wilt for two minutes, stirring all the time.

Add the boiling water, season with four pinches of salt and a pinch of pepper and boil rapidly for no longer than two minutes. Add the ice to stop the cooking. Purée the soup in a jug blender until smooth.

Just before serving, reheat the soup. Taste and correct the seasoning if required. You may want to finish this lovely soup with a swirl of crème fraîche or simply top it with a sprig of fresh watercress.

Recipe taken from Le Manoir Aux Quat’Saisons: The Story of a Modern Classic by Raymond Blanc (Bloomsbury). To order a copy of the 'Kitchen Edition’ for £42 (rrp £50) with free p&p, or the 'Special Edition’ for £200 (rrp £250) with free p&p, call 0844 871 1514 or visit books.telegraph.co.uk