COLD BEET AND CELERY SOUP

Cold Beet and Celery Soup image

Yield Makes about 7 cups

Number Of Ingredients 9

1 cup finely chopped onion
2 cups thinly sliced celery
2 tablespoons olive oil
2 teaspoons sugar
1 1/2 pounds beets, peeled and cut into 1-inch pieces
1 tablespoon red-wine vinegar plus additional to taste
3 cups low-salt chicken broth
ice water for thinning soup
sour cream, seasoned with bottled horseradish, and minced fresh chives for garnish

Steps:

In a heavy saucepan cook onion and celery in oil with sugar and salt and pepper to taste over moderately low heat, stirring, until softened and add beets, 1 tablespoon vinegar, and broth. Simmer mixture, covered, 35 to 40 minutes, or until beets are very tender.
In a blender purée mixture in batches until very smooth, transferring as puréed to a bowl. Chill soup, covered, at least 6 hours or overnight.
Thin soup with ice water and season with additional vinegar and salt and pepper.
Garnish soup with sour cream and chives.