Leek and Potato Soup (Vichyssoise)

Ingredients: 2 1/2 cups chicken stock (or broth for Vichyssoise),2 tablespoons chopped fresh flat-leafed parsley leaves (wash and dry before chopping),1 garlic clove, minced,3 tablespoons half and half (or cream for Vichyssoise),2 mediums leeks (white parts only), halved lengthwise, washed well, and sliced thin crosswise,1/2 medium onion, chopped fine,1 medium boiling potato (about ½ pound),1 tablespoon unsalted butter,Note: For Vichyssoise, omit parsley and add snips of fresh chives.
Instructions:

1. Peel potato and dice fine. In a 3 1/2- to 4-quart saucepan cook garlic and onion and leek in butter over moderately low heat, stirring, until onion is softened.
2. Add potato and cook, stirring occasionally, 2 minutes. Stir in stock or broth and simmer, uncovered, 15 minutes, or until potato is very tender.If desired, in a blender pure soup in batches until very smooth (use caution when blending hot liquids), transferring to another saucepan. Stir in cream, parsley, and salt and pepper to taste and heat over moderate heat, stirring occasionally, until hot.
3. Serve
4. For Vichyssoise, puree the soup until smooth and season with salt and white pepper to taste. Chill.
5. Add snips of chive to bowls filled with the soup and serve.

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