Vichyssoise

Method

1. 1

   Soften the vegetables

   Melt the butter in a large saucepan over low heat. Add the leeks and onion and cook for 10 minutes, stirring often, until very soft and translucent without browning.

2. 2

   Cook the potatoes

   Add the potatoes and stock, bring to a gentle simmer over medium heat, then cover and cook over low heat for 20 minutes, until the potatoes break easily when pressed with a fork.

3. 3

   Blend the soup

   Remove the pan from the heat and blend the soup until completely smooth, about 2 minutes, working in batches if needed and keeping the blender no more than half full.

4. 4

   Finish and chill the soup

   Stir in the cream, 1 teaspoon salt and white pepper, then taste and add salt in small pinches until well seasoned; transfer to a shallow container and chill for at least 2 hours, until cold.

5. 5

   Bake the croutons

   Heat the oven to 180°C. Toss the bread cubes with the olive oil and a pinch of salt, spread on a baking tray and bake for 8 to 10 minutes, until crisp and lightly golden, then cool.

6. 6

   Adjust the consistency

   Stir the chilled soup and check its texture; if it is thicker than you like, whisk in cold stock or water 1 tablespoon at a time until smooth and pourable.

7. 7

   Serve

   Ladle the cold soup into four bowls and garnish with chives and croutons immediately before serving.

Tips

• Rinse sliced leeks thoroughly because grit can lodge between the layers.
• Use low-salt stock so you can season the soup accurately at the end.
• Cool the soup in a shallow container rather than leaving a large hot pan to cool on the counter.
• Add croutons only at serving so they stay crisp.

Swaps

• Use vegetable stock instead of chicken stock.
• Use olive oil instead of butter.
• Use finely sliced spring onion instead of chives.

Storing

Refrigerate covered for up to 3 days. Keep croutons in an airtight container at room temperature for up to 2 days. Stir the soup before serving chilled.