Prep: Wash and halve cherry tomatoes, and halve mozzarella balls. Roll basil leaves together vertically and then make thin slices across the roll so that you end up with basil ribbons.
Combine: Place tomatoes, basil and mozzarella into a large mixing bowl and stir gently to combine.
Drizzle: Drizzle everything with olive oil and vinegar, and season with salt and pepper to taste.