Cook pasta according to package directions until al dente. Drain and rinse under cold water to cool.
While pasta cooks, drain canned chicken and flake with a fork.
In a large bowl, whisk together mayonnaise, Greek yogurt, apple cider vinegar, Dijon mustard, garlic powder, salt, and pepper.
Add cooled pasta, flaked chicken, red bell pepper, celery, red onion, and parsley to the bowl. Toss until everything is well coated.
Taste and adjust seasoning with more salt, pepper, or vinegar if needed.
Refrigerate for at least 30 minutes before serving to allow flavors to meld. Serve cold or at room temperature.
