Preheat oven to 350°F (175°C) or 400°F (200°C).

Trim off the hard edges of the cornbread.

Crumble the cornbread and biscuits into a large mixing bowl until finely textured.

Add chicken broth gradually, mixing until the consistency is similar to mashed potatoes or slightly thinner.

Incorporate the chopped onion and celery into the mixture.

Season with salt, pepper, and poultry seasoning to taste.

Add the well-beaten egg and mix thoroughly.

Pour the mixture into a greased 9 x 13-inch pan and a smaller pan, if needed.

Bake for approximately 40 minutes, or until golden brown and cooked through.