Pre-heat your oven to 250 degrees Fahrenheit.
Spread the torn pieces of bread out between two rimmed baking sheets.
Bake the bread in your pre-heated oven, tossing occasionally, until it’s dry and crisp, usually 50-60 minutes.
Remove the baking sheets from your oven and set them aside to cool.
Once cooled, transfer the bread to a very large bowl.
The bread can also be baked 1-2 days in advance and stored in an airtight container at room temperature until you're ready to make the stuffing.
Increase your oven temperature to 350 degrees.
Lightly spray a 9 X 13-inch baking dish with non-stick cooking spray and set it aside.
In a large heavy-bottom pot over medium heat, melt 1/2 cup of the butter (not of it!) with the olive oil.
Add the celery, onion and fennel and cook, stirring occasionally, for 15 minutes.
Stir in the apple, salt, pepper and the remaining 1/2 cup of butter and cook for an additional 6-8 minutes.
Remove the pot from the heat. Stir in all the herbs. Set aside.
In a medium bowl, whisk together the vegetable broth and eggs.
Slowly pour this mixture over the bread in the bowl.
Then scrape the cooked vegetables/herbs (and any accumulated liquid in the pot) on top. Gently fold/toss everything together, making sure all the bread is moistened and the ingredients are well combined.
Transfer the stuffing to your prepared baking dish, packing it down lightly. Cover the baking dish with aluminum foil and transfer to your pre-heated oven for 40 minutes.
Carefully remove the aluminum foil and increase the oven temperature to 425 degrees. Continue baking the stuffing uncovered for 25 minutes.
The top should be golden brown and crisp. Remove it from the oven and set it aside to rest for 10 minutes before serving.
Leftovers can be stored in an airtight container in your refrigerator for 2-3 days.