1. In food processor, add green onion, cucumber (leave one for garnish), lemon zest, lemon juice, garlic, salt, pepper, and 1/3rd of the chopped tomato. Blend well.
2. Add the remaining tomato and puree until smooth. Add parsley and basil. Blend again.
3. Into a bowl, transfer the soup and refrigerate for an hour.
4. Garnish with cucumber and croutons and serve chilled.