Drain the mozzarella and cut into slices. Wash, clean and slice the tomatoes. Cut the rolls in half and spread with garlic butter. Cover the lower halves of the rolls with a slice of mortadella, some tomato and mozzarella slices and basil leaves. Sprinkle with pepper.
Place the upper halves of the rolls on top. Place two rolls in the sandwich toaster and press them together. Toast for about 3 minutes. Arrange on a plate with lettuce leaves, olives and tomato slices as desired