Place the almonds in a skillet over medium-low heat and toast them gently, stirring often until they become golden and fragrant without burning.
In a medium bowl, combine the mayonnaise, lemon juice, and black pepper, mixing until the dressing is smooth and well blended.
Add the chopped chicken, toasted almonds, and celery into the bowl with the dressing.
Toss everything together gently until all ingredients are evenly coated without overmixing.
Serve immediately or refrigerate for a short time before serving for better flavor.