Blanch and peel the tomatoes, remove the seeds and dice them. Core the olives and dice them too. Slice the parmesan into fine strips, the strips should be approx. 2-3 cm long. Finely chop the basil, mix everything, pour vinegar and oil over them, pepper. Pour into a tightly closing vessel and let it steep in the refrigerator overnight. A tablespoon of chopped capers can also be used in place of the olives.