Vichyssoise

Despite its French name, Vichyssoise was created in New York around 1917 by French-born chef Louis Diat, who modelled it on the warm leek and potato soup of his childhood in the Allier region. Served ice-cold, it has become a French-American classic of refined simplicity.

Serves: 6

Ingredients

• 4 large leeks (about 700g / 1.5 lb), white and pale-green parts only, sliced
• 400g (14 oz) waxy potatoes, peeled and diced
• 1 medium onion, roughly chopped
• 30g (2 tbsp) unsalted butter
• 1 litre (4 cups) low-sodium chicken or vegetable stock
• 200ml (¾ cup) single cream or crème fraîche
• Salt and white pepper to taste
• 2 tbsp snipped fresh chives, to serve

Instructions

1. Melt the butter in a large saucepan over medium-low heat. Add the leeks and onion, cover, and sweat without colouring for 10–12 minutes until completely soft.
2. Add the potatoes and stock. Bring to a simmer, then cook uncovered for 20 minutes until the potatoes are very tender.
3. Remove from heat and blend until completely smooth using a stick blender or upright blender. Pass through a fine sieve for an extra-silky texture.
4. Stir in the cream, then season lightly with salt and white pepper. The stock should supply most of the seasoning — taste before adding salt.
5. Transfer to a container, press cling film directly onto the surface, and refrigerate for at least 3 hours or overnight until thoroughly chilled.
6. Serve in chilled bowls, topped with snipped chives and a light drizzle of cream if desired.

Cook's Notes: Use a good-quality low-sodium stock — the soup has no other seasoning base, so the stock quality matters. Vichyssoise keeps refrigerated for up to 3 days. For a lighter version, replace cream with plain yoghurt stirred in just before serving.