Start by cooking the pasta according to package instructions. Add the chopped sun-dried tomatoes with 3-4 minutes left in the pasta time. Drain.
Meanwhile, in a medium bowl, combine chopped fresh tomatoes, balsamic vinegar, olive oil, garlic, red onion, red pepper flakes and the fresh herbs. Stir to combine thoroughly.
Add the pasta to the other ingredients and stir to combine. Add the fresh mozzarella and stir again.