Combine all ingredients in a blender or food processor (except bread and limes), and puree until smooth. Transfer to a large bowl and refrigerate for 4 hours. Meanwhile prepare relish.
Relish: Combine and chill for 1 hour. Ladle out soup into pretty bowls, top with a large tablespoon of relish, 1 crouton, and a slice of lime.
Yield: 6 servings