In a large bowl, combine the olive oil, basil (save a few leaves for serving) and garlic.
Add the tomatoes and mix well. Set aside.
Cook the pasta in plenty of boiling water, according to package instructions.
Cut the mozzarella into small pieces. Add the pieces to the sauce.
Once the pasta is cooked, drain it but save a small glass of cooking water [to bind the sauce]. Add 2 tbsp. of cooking water to the sauce.
Pour the pasta over the sauce, mix and coat well. Add a little cooking water if necessary.
Season with salt and pepper and sprinkle with basil leaves.