Boil the rice and set it aside. Cut the tomatoes into 4 parts and season with oil, salt and basil and let them rest an hour in the refrigerator.
Drain the mozzarella and let it dry on a paper towel.
In a salad bowl put the cooled rice, add the seasoned tomatoes, mozzarella and taggiasca olives. Mix well, season with salt and oil and garnish with the remaining basil leaves.