Asparagus And Leek Vichyssoise

• 2 medium leeks

• 1 pound asparagus (you can use thick or thin stalks for this)

• 1 large potato, about 8 ounces (I like to use Yukon Gold)

• 2 tablespoons unsalted butter

• 3 cups vegetable or chicken stock

• Kosher salt and freshly ground black pepper

• 1/4 cup heavy cream

• 1/4 cup Greek yogurt or sour cream, for serving

• Grated zest of 1/2 lemon

1. Chop off and discard the tough green ends of the leeks. Cut through the leeks lengthwise and wash them out completely. Cut crosswise into half-moons; set aside.

2. Trim off and discard the tough, woody ends of the asparagus. Cut spears into 1-inch pieces, keeping the tips separate; set spears aside.

3. Peel and roughly dice the potato.

4. Heat butter in a large saucepan over medium heat. Add leeks, chopped asparagus spears (not the tips) and potato to the saucepan, stirring to coat with the butter. Cook, tossing occasionally, for 4 minutes, making sure the leeks, spears and potatoes don't brown at all. Stir in stock and season with a bit of salt and pepper. Bring to a boil, cover and reduce heat to a gentle simmer. Cook until vegetables are tender, about 40 minutes. Stir in asparagus tips and cook for 10 minutes.

5. Puree the soup in batches until very smooth. Transfer to a bowl or large plastic container and stir in cream and yogurt. Season to taste with salt and pepper. Bring soup to room temperature and then chill. Serve with a dollop of yogurt or sour cream and sprinkle with lemon zest.

Serves 4 to 6