Preheat oven to 350 degrees. Spray a 9x13 casserole dish with non-stick cooking spray.
Brown sausage in a medium skillet. Remove sausage to drain.
Add the onion and celery to the skillet. Cook over medium heat, stirring as needed to avoid burning, until softened.
In a large bowl, stir together sausage, vegetables, cornbread, French bread, and seasonings. Stir until evenly combined.
Add up to 2 cups of chicken stock half cup at a time to moisten the bread and bring the ingredients together.
Transfer to casserole dish and distribute evenly. Bake for 30 minutes.
Notes
I recommend adding the broth in increments. Once all of the ingredients are combined, assess. Is the mixture still a bit dry? Go ahead and add the rest of the broth. If it's quite moist already, don't.Just how dry your bread is determines how much moisture to add. It's a little bit variable and depends on if you prefer a more dry or moist stuffing.