Prep chicken: Dice cooked chicken into ½-inch cubes. Pat completely dry with paper towels.
Toast pecans: Toast in dry skillet over medium heat 4-5 minutes until fragrant. Cool and chop.
Prep ingredients: Dice celery finely. Halve grapes. Mince onion. Chop pineapple, draining well.
Make dressing: Whisk mayonnaise, sour cream, pineapple juice, lemon juice, honey, salt, white pepper, and garlic powder until smooth.
Combine: Mix chicken, celery, grapes, pecans, pineapple, onion, and parsley in large bowl.
Dress: Pour dressing over mixture. Fold gently until evenly coated.
Chill: Cover and refrigerate minimum 1 hour for flavors to meld.
Serve: Stir before serving. Adjust seasoning if needed. Serve on croissants, bread, or lettuce cups.