Baked Chicken with whites

3 or 4 frozen or thawed, boneless and skinless chicken breasts ¼ teaspoon salt or to taste ¼ teaspoon ground black pepper or to taste 1 can (14 ounces)[...]

4 cups chopped cooked chicken breasts 1 cup mayonnaise 1/4 cup chopped onion 1 1/2 cups chopped celery 4 hard-boiled eggs , chopped 1 (4 ounce) can chopped[...]