How to Make It
Process chopped heirloom tomatoes, bread, oil, vinegar, salt, cayenne pepper, and 1 cup of the chopped cucumber in a blender until smooth. Transfer to a bowl. Stir in cherry tomatoes and remaining 1 cup chopped cucumber. Chill 1 hour. Ladle gazpacho into each of 4 bowls; dollop evenly with sour cream.