Bring a large pot of salted water to a boil and cook the rotini according to the package directions until al dente.
Drain the pasta and rinse under cold water until completely cooled.
In a large mixing bowl, combine the cooled pasta, salami, mozzarella, cherry tomatoes, bell pepper, red onion, black olives, pepperoncini, and parsley.
In a small bowl, whisk together the Italian dressing, olive oil, red wine vinegar, Italian seasoning, garlic powder, black pepper, and Parmesan cheese.
Pour the dressing over the pasta salad.
Toss gently until everything is evenly coated.
Cover and refrigerate for at least 30 minutes before serving for the best flavor.
Toss again just before serving.