In a skillet over medium heat, cook the bacon until crispy, about 8-10 minutes, stirring occasionally. Transfer to a plate lined with paper towels to drain excess fat and cool.

Bring a large pot of salted water to a rolling boil, then add the frozen cheese tortellini. Cook according to package instructions until al dente, around 3-5 minutes. Drain and rinse under cold water.

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

Add the cooled tortellini, crispy bacon, chopped pepperoncini, grated Parmesan cheese, diced red onion, and sliced tomatoes to the bowl with the dressing. Gently toss everything together.

Cover the bowl and refrigerate for at least 2 hours.

Before serving, give the salad a gentle stir, taste, and adjust the seasoning with additional dressing if needed.