Ingredients

  • 2 tablespoons (60g) butter
  • 2 leeks, trimmed (white and pale green parts only) and sliced, or 1 large onion, sliced
  • 1 large, starchy potato (about 8 ounces/250g), peeled and cut into large chunks
  • 1 quart vegetable stock
  • 2 cucumbers, peeled and cubed
  • 2 Little Gem or butterhead lettuces, shredded
  • 3 tablespoons heavy cream or creme fraiche
  • Sea salt and freshly ground black pepper
  •  
  • 1/4 cup (60ml) canola or olive oil
  • 4 slices of bread, crusts removed, cut into cubes
  •  
  • Chopped chives
  • Heavy cream or creme fraiche

Method

  • Melt the butter in a large saucepan over medium-low heat. Add the leeks or onion, cover, and sweat gently for about 10 minutes, until soft. Add the potato and stock. Bring to a boil, then simmer for about 10 minutes, until the potato is almost cooked. Add the cubed cucumbers and shredded lettuce, return to a boil, and simmer for a further 4 minutes.
  • Scoop out the potato chunks and rub them through a sieve, run them through a food mill, or press them through a potato ricer into a large bowl (whizzing them in a blender would make the soup gluey). Puree the simmered mixture in a blender, add to the sieved potato, and stir well. Stir in the cream or creme fraiche and season with salt and pepper. Leave to cool completely, then chill for a couple of hours.
  • Meanwhile, make the croutons. Heat the oil in a frying pan over medium-high heat. Add the bread and fry, turning often, for a few minutes, until golden brown. Leave to cool.
  • Serve the chilled soup topped with a swirl of cream or creme fraiche, chopped chives, and croutons.