Cut one avocado in half, remove the pit, and scoop the flesh into a large mixing bowl.
Add the mayonnaise (or mayonnaise and Greek yogurt mixture), chopped celery, chopped onion, cilantro, lime juice, and kosher salt.
Mash the avocado until mostly smooth and stir everything together to create a creamy dressing.
Add the shredded cooked chicken and gently mix until evenly coated.
Dice the remaining avocado into bite-sized cubes and carefully fold it into the salad to maintain its texture.
Taste and adjust with additional salt, freshly ground black pepper, or extra lime juice if desired.
Serve the Creamy Avocado Chicken Salad immediately or chill for 30 minutes to allow the flavors to develop.
Enjoy it with crackers, tortilla chips, toasted bread, croissants, wraps, lettuce cups, or over a bed of mixed greens