Prepare corn bread mix according to package directions. Let cool and crumble into bite size pieces.
Add butter to a large skillet over medium heat and saute the celery and onion for a few minutes until soft.
In a large bowl, combine celery, onion, crumbled corn bread, eggs, chicken stock, sage and salt and pepper.
Spread mixture in a 9x13 inch baking pan sprayed with nonstick cooking spray.
Bake for 35-40 minutes, or until cooked through and center is set.
Notes
To make this ahead of time, make it all the way through step #5. Then just stick in the oven and cook on Thanksgiving.Make sure that you use a cornbread mix and NOT a cornbread STUFFING mix. Prepare the cornbread as directed on the package and then when it cools, you crumble it up and use that to make your stuffing.