Cook the rotini pasta in a large pot of salted boiling water until al dente, approximately 8 to 10 minutes.
Drain the pasta and rinse under cold water until fully cooled to prevent sticking and stop the cooking process.
In a large mixing bowl, whisk together the mayonnaise, sour cream, white wine vinegar, granulated sugar, Dijon mustard, garlic powder, onion powder, dried parsley, salt, and black pepper until smooth.
Incorporate the diced red bell pepper, diced cucumber, diced red onion, sliced celery, and halved cherry tomatoes into the dressing.
Add the cooled pasta to the bowl and fold gently until all ingredients are evenly coated.
Cover and refrigerate for a minimum of 2 hours before serving to allow the dressing to set and flavors to develop.