Adjust oven rack to the center position and heat the oven to 350˚F.
Cook the bacon in a large skillet over medium heat until crisp and brown, about 10-12 minutes.
Transfer the bacon to a paper towel-lined plate.
Add the celery, onion, and apple to the same skillet the bacon was cooking in (don’t drain off the bacon grease) and sauté, stirring occasionally, until softened about 8-10 minutes.
Add the parsley, thyme, sage, and marjoram and stir. Cook until fragrant, about 1 minute. Transfer the mixture to a large mixing bowl.
Add the breadcrumbs, egg, salt, pepper, chicken broth and bacon to the vegetable and apple mixture.
Place the stuffing mixture into a buttered 9x13 pan, or any other 3-quart pan. Bake for 45 minutes, or until the top is golden brown and the internal temperature reaches 165˚F.