BEST SOUTHERN CORNBREAD DRESSING WITH CHICKEN

Traditional Southern holiday dish, but enjoyed any time. Cornbread dressing is baked with the addition of cooked chicken.
INGREDIENTS :
1 10-inch cast-iron skillet of baked, cooled and crumbled unsweetened cornbread
5 slices 2-day-old white bread, crusts removed
1 medium onion, chopped (about 3/4 c)
2 ribs celery, chopped (1/2 c)
1 stick butter or margarine, divided
2 jumbo eggs
4 – 5 cups chicken stock or broth*
1/2 teaspoon poultry seasoning, optional
1/2 teaspoon ground black pepper
Salt, to taste (optional)
4 – 5 cooked chicken breasts, chopped (I boiled them)
2 hard-boiled eggs, chopped (optional)(I omitted this time)
DIRECTIONS :
Bake and cool your favorite cornbread recipe; then crumble and set aside. *(I prepared 2 pouches Martha White Yellow Cornbread & Muffin Mix as directed on package, then cooled, crumbled, and laid out on jellyroll pan to dry out a bit.)
Remove crusts from bread and tear into pieces then pulse in a food processor into crumbs but not too fine. Pour crumbs onto a jellyroll pan and place it in a warm oven for 20-30 minutes to dry out. Let cool on a wire rack.
Meanwhile, saute the onion and celery in 6 tablespoons butter, then set aside.
Preheat oven to 350° F. Lightly spray a 13×9 baking dish with cooking spray …