Shred the cooked chicken into bite-sized pieces and place in a large mixing bowl.
In a small bowl, whisk together the buffalo sauce, mayonnaise, lemon juice, garlic powder, and black pepper until smooth.
Pour the dressing over the shredded chicken and mix until all the chicken is evenly coated.
Add the diced celery, grated carrot, and sliced green onions to the bowl.
Gently fold everything together until well combined.
Taste and add salt if needed—remember that buffalo sauce can be salty.
Cover the bowl and refrigerate for at least 30 minutes to let the flavors meld.
Serve cold on bread, crackers, or over greens.