Buttermilk Vichyssoise with Watercress

• 3 tablespoons unsalted butter
• 4 leeks, white and light green parts only, halved lengthwise and then thinly sliced into half-moons, washed well and drained
• 3 large white potatoes, peeled and cut into 1-inch pieces
• 4 1/2 cups homemade or low-sodium store-bought chicken stock
• 3 cups cleaned watercress leaves, loosely packed
• Coarse salt and freshly ground white pepper
• 1 cup half-and-half
• 1 cup buttermilk

1. Melt the butter in a stockpot over medium-low heat.
2. Add the leeks, and cook, covered, until tender, about 15 minutes.
3. Add the potatoes, stock, and 2 cups water.
4. Bring to a boil; simmer until the potatoes are tender, about 20 minutes.
5. Cool completely; stir in 2 cups of the watercress.
6. Working in batches, puree the soup in a blender until smooth.
7. Transfer the pureed soup to a large bowl.
8. Season with salt and white pepper.
9. Stir in the half-and-half; chill at least 1 hour.
10. Add the buttermilk just before serving.
11. Adjust seasoning; if necessary, thin the soup with a bit more chicken stock or water to achieve the desired consistency.
12. Garnish with the remaining cup watercress leaves.

unsalted butter, leeks, white potatoes, chicken, watercress leaves, salt, buttermilk

Taken from www.epicurious.com/recipes/food/views/buttermilk-vichyssoise-with-watercress-392283 (may not work)