To dry the cornbread, preheat the oven to 250 F and bake the cornbread muffins for 30 minutes, tossing halfway through. Set aside on the counter.
Preheat the oven to 350 F and lightly grease an 8×8″ casserole dish.
Using a medium skillet, heat the avocado oil over medium heat. Add the onion, and celery and saute for 5-6 minutes or until lightly tender. Stir in the apple for another 2 minutes to lightly soften. Set aside.
In a smaller bowl, whisk the broth and egg together. Set aside.
Prepare a bowl with the corn muffin cubes and add the celery, onion, dried cranberries, seasonings, and broth mixture. Toss the entire mixture together with a rubber spatula to fully combine. The mixture will be soft and wet.
Add the stuffing mixture to the baking dish and cover. Bake in the preheated oven covered for 25 minutes. Remove the cover and bake for another 12-15 minutes or until lightly golden brown.
Serve topped with additional thyme and dried cranberries.