Preheat the oven to 375°, and lightly butter a medium-sized casserole dish.

In a large, non-stick skillet set over medium-high heat, add the olive oil; once the oil is hot, add in the spicy Italian sausage, crumbling it into the pan and using a spoon/spatula to break it up.

Allow the sausage to cook for a couple of minutes, and then add in the celery, onion, and garlic, plus a pinch of salt and pepper, and stir the mixture together allowing it to cook until the veggies and sausage are a light golden-brown; once golden, remove from the pan and set aside for a moment.

Into a large bowl, begin tearing bite-size pieces of the French bread.

Add to the torn bread the sauteed veggies and spicy sausage mixture, along with the parsley, sage, fresh thyme leaves, ½ teaspoon of the Italian seasoning, dry thyme, the ½ teaspoon of salt and pepper, and the chopped dried apples, and toss the mixture together.

Next, add in the warm chicken stock, the melted butter, the beaten eggs, 1 cup of the shredded Italian four-cheese blend, and the parmesan, and combine very thoroughly.

Once well mixed, turn the homemade stuffing mixture into the buttered casserole dish and top with the remaining ½ cup of shredded Italian four-cheese blend and ½ teaspoon of Italian seasoning; cover the casserole dish with foil, and place the dish into the oven to bake for 30 minutes.

After 30 minutes, remove the foil from the casserole dish, place casserole back into the oven, and bake an additional 15 minutes, or until golden-brown on top, and puffy.