Green heirloom tomatoes gives this gazpacho its vibrant hue, and sets it apart from the traditional red variety. To keep the gazpacho from being too thin (tomatoes release a lot of juices when pureed), sliced bread is added to thicken the soup. Olive oil gives it its creamy texture, while cayenne pepper and red wine vinegar amp up the flavor and lend some zest. Be sure to let the gazpacho refrigerate before servingafter all, this is a chilled soupthen top each bowl with a dollop of sour cream. Its the perfect dish to serve at a late-summer dinner party.