In a large mixing bowl, combine the shredded chicken, diced red onion, diced celery, red grapes, and chopped pecans.
In a separate bowl, whisk together the mayonnaise, sour cream, Dijon mustard, and honey until well combined.
Pour the dressing over the chicken mixture and toss until everything is evenly coated. Season with salt and pepper to taste.
Cover the bowl and refrigerate for at least 30 minutes to allow the flavors to meld.
When ready to serve, place fresh lettuce leaves on plates and spoon the chicken salad on top.
Garnish with extra pecans or grapes if desired.