Preheat the oven to 350°F. Heat the ghee in a 10-inch cast-iron skillet over medium-high heat until melted. Swirl it around to coat the bottom and sides of the skillet, then pour the melted ghee into a large bowl. Place the cast-iron skillet back on the stovetop and keep on low heat.
Add the almond milk, honey, and vinegar to the mixing bowl and mix with a whisk for 30 seconds. Add the eggs, one at a time, beating in after each addition. Add the almond flour, coconut flour, baking powder, baking soda, rosemary, sage, and salt and mix until combined. Pour the batter into the hot cast-iron skillet.
Bake for 30 minutes, or until the bread is golden and a toothpick inserted into the center comes out clean when. Cool for 20 minutes.
Cut “corn” bread into 1/2-inch cubes and lay on a baking sheet. Turn you broiler on high and broil the pieces for 2-4 minutes or until lightly browned and crispy. Remove and set aside.
Coarsely chop separately celery, onions, and bacon. In a large, deep skillet sauté bacon over moderately high heat, stirring, until browned, about 10 minutes. Add celery and onions and cook, stirring, until vegetables are softened, about 5 minutes. Add herbs and salt and pepper to taste and cook, stirring, 1 minute.
In a large bowl toss together corn bread and bacon mixture and transfer to baking dish. In a small microwave safe bowl, add broth and microwave for 30 seconds. Add collagen to broth and stir until combined.
Drizzle stock or broth over stuffing and bake, covered, for 45 minutes at 350 degrees.