Bring a large pot of salted water to a rolling boil. Add the rotini pasta and cook according to package directions until al dente, about 9-10 minutes.

While pasta cooks, prepare the dressing. In a medium bowl, whisk together mayonnaise, red wine vinegar, pepperoncini juice, oregano, garlic powder, black pepper, red pepper flakes, and salt until smooth and creamy.

Drain the cooked pasta and rinse under cold water for 20 seconds. Shake off all excess water thoroughly and transfer to a very large mixing bowl.

Add the diced salami, ham, pepperoni, provolone cheese, cherry tomatoes, pepperoncini, red onion, and banana peppers to the bowl with the pasta.

Pour about two-thirds of the dressing over the mixture and toss gently to coat everything evenly. Reserve the remaining dressing.

Cover tightly and refrigerate for at least 2 hours, preferably 4 hours or overnight to allow flavors to meld.

Right before serving, gently stir in the remaining dressing and fresh basil. Taste and adjust seasoning if needed. Serve chilled.