1. Prepare a food processor with the blade attachment.
2. Pack the measuring cup with basil leaves and place in the food processor. Process until leaves are finely chopped, then stop and scrape down the sides.
3. Peel cucumbers, roughly chop, then place in the food processor.
4. Peel green apples, roughly chop (discarding the core), and add to the food processor. Process until ingredients are finely chopped, then stop and scrape the sides again.
5. Slice the avocado in half lengthwise and twist both halves to separate. Stab the pit with the knife blade and twist to release. Scoop flesh into the food processor. Reserve a few chunks for final garnish, if desired. Add champagne vinegar and olive oil. Process until mixture is smooth.
6. With motor running, drizzle in a little cold water, enough so water mixture is loose but not watered down. Let food processor run until soup is well pureed. Season with salt and pepper to taste, then pour into a large bowl. Cover and refrigerate for 10-15 minutes or until the rest of your meal is ready.
7. If garnishing with tomato, cut into small dice.
1. Ladle cucumber gazpacho into soup bowls. Garnish with diced tomato or other preferred toppings and serve cold!