Can be prepared in 45 minutes or less.
Makes about 4 1/2 cups, serving 4 to 6.
INGREDIENTS
DIRECTIONS
In a large saucepan cook the onion, the celery, and the carrot in the butter over moderately low heat, stirring, until the vegetables are tender, stir in the broth and the rosemary, and bring the mixture to a boil. Whisk in the potatoes, a little at a time, bring the soup to a boil, whisking, and stir in the vinegar, the parsley, and salt and pepper to taste.