In a large skillet, cook the bacon over medium heat until crispy and golden brown, about 8–10 minutes. Transfer to paper towel to drain and chop into bite-sized pieces.

Bring salted water to a boil in a large pot. Add the cheese tortellini and cook according to package instructions, usually 3–5 minutes, until al dente. Drain and rinse under cold water.

In a mixing bowl, combine mayonnaise, red wine vinegar, salt, oregano, Italian seasoning, garlic powder, and red pepper flakes. Whisk until smooth.

Add the cooled tortellini to the dressing. Mix in the chopped bacon, red onion, cherry tomatoes, pepperoncini, and Parmesan cheese. Toss gently to coat all ingredients.

Cover the bowl with plastic wrap and refrigerate for at least 2 hours to allow flavors to meld.

Before serving, stir the salad and add a splash of reserved dressing if needed. Serve chilled.