For the gazpacho, first roughly chop the onion. Crush 2 cloves of garlic. Rinse tomatoes, cucumber and zucchini and chop coarsely. Rinse the bell bell pepper, remove the seeds and chop coarsely as well. Finely puree the vegetables with a cup of tap water.
Empty the vegetable puree into a bowl and whisk in the oil and vinegar. Season the soup with pepper and sea salt. If it is too thick, add a tiny bit more tap water and whisk until creamy.
Place the gazpacho in the ice chest for 1 1/2 hours. Then remove from the ice chest and give it another good stir. Divide among glasses or bowls and garnish with the diced tomatoes, peppers, cucumber and a basil leaf each.