In a skillet over medium heat, cook the bacon until crispy, about 8–10 minutes. Remove and chop into bite-sized pieces.

Bring a large pot of salted water to a boil. Add the tortellini and cook according to package directions, typically 3–5 minutes. Drain and rinse under cold water.

In a large mixing bowl, whisk together the mayonnaise, red wine vinegar, salt, oregano, Italian seasoning, garlic powder, and red pepper flakes.

Add the cooled tortellini, pepperoncini, Parmesan cheese, red onion, cherry tomatoes, and chopped bacon to the bowl. Gently fold together.

Cover and refrigerate for at least 2 hours or up to overnight before serving.