AVOCADO CREMA: Mash avocado in medium bowl until smooth. Stir in sour cream, lime juice and sugar. Refrigerate while preparing Gazpacho.
GAZPACHO: Combine all remaining ingredients except basil. Pour half into blender; blend until smooth. Add to remaining tomato mixture with basil; mix well. Refrigerate 2 hours.
SERVE Gazpacho topped with Avocado Crema.