In a small bowl, mix mayonnaise, mustard, greek yogurt, honey, lemon juice, dried dill, black pepper and set aside for later.
In a large bowl, mix shredded chicken, celery, grapes, walnuts, green onion and red onion. Pour in dressing and mix to fully combine.
Cover salad with plastic wrap or place in an airtight container in the fridge for at least 30 minutes to allow the flavors to fully develop. Serve chicken salad on toasty sliced bread, crackers or a warm croissant. Enjoy!