Make the dressing. Combine the olive oil, garlic powder, basil, oregano, salt, pepper, onion powder, and Dijon dressing in a small bowl. Add the vinegar while whisking until well-combined.
Add the other ingredients and chill. In a large mixing bowl, combine the cooked pasta with the dressing and add the cucumber, tomato, and mozzarella. Cover the pasta salad and chill in the fridge for at least two hours.
Serve. Remove from the fridge and add the fresh parsley. Stir again to combine.
Notes
If you make this ahead of time, you might need to add a tiny bit of oil again before serving if it seems dry.