Gather the ingredients including cooked chicken breast, ripe avocados, diced red onion, chopped celery, chopped fresh cilantro, lime juice, salt, and pepper.
Cook the chicken breast by grilling, baking, or poaching it until fully cooked. Once cooked, allow it to cool slightly, then dice or shred it into bite-sized pieces.
Halve the ripe avocados and remove the pits. Scoop the avocado flesh into a mixing bowl using a spoon, and mash it slightly with a fork.
Add the diced red onion, chopped celery, chopped fresh cilantro, lime juice, salt, and pepper to the mashed avocado in the mixing bowl. Stir until well combined.
Add the diced or shredded cooked chicken breast to the avocado mixture in the mixing bowl.
Gently fold the chicken into the avocado mixture until it is evenly coated with the avocado dressing and all the ingredients are well combined.
Taste the avocado chicken salad and adjust the seasoning as needed, adding more salt, pepper, or lime juice to suit your preferences.
Once the avocado chicken salad is seasoned to your liking, you can serve it immediately as a sandwich filling, on top of a bed of greens, or with crackers or bread for a light and satisfying meal.