- 1 large leek (2 inches of green left on)
- 2 tablespoons white vinegar
- 2 tablespoons olive oil
- 2 tablespoons unsalted butter
- 1 onion, peeled and chopped
- 1 parsnip, peeled and chopped
- 6 cups defatted chicken broth
- 2 to 3 tablespoons chopped fresh tarragon leaves
- 2 pounds medium-sized asparagus, ends trimmed
- 1/3 to 1/2 cup heavy (or whipping) cream
- 15 small cantaloupe or watermelon balls, for garnish
- 20 small fresh mint leaves, for garnish
- 1/3 cup sour cream, for garnish
- Remove the root and tough outer leaves from the leek; halve lengthwise. Soak in vinegar and water to cover for 30 minutes. Rinse. Cut into 1/4-inch dice.
- Heat the oil and butter in a pot. Add the leek, onion and parsnip; cook over low heat to soften, 15 minutes.
- Add the broth and tarragon; bring to a boil. Add the asparagus; cover, then simmer for 30 minutes or until very tender. Uncover and cool.
- Puree the soup. (If it seems stringy, pour through a strainer.) Add the cream. The soup may be served chilled or reheated over low heat; do not boil. Serve 1 1/2 cups of soup per bowl, placing 3 melon balls in the center of each serving, surrounded by 4 mint leaves. Add a dollop of sour cream on one side of each bowl.