Gather all ingredients. Preheat the oven to 375 degrees F (190 degrees C). Grease a deep 9x13-inch baking dish or roasting pan.

Heat a large skillet over medium-high heat, Add sausage; cook and stir until crumbly, evenly browned, and no longer pink. Drain and discard any excess grease.

Transfer sausage to a large bowl.

Meanwhile, heat pancetta and olive oil in the same skillet over medium heat until it begins to brown. Stir in celery and onions; cook until onions soften and turn translucent, about 8 minutes.

Stir in garlic; cook until aroma mellows, about 3 minutes.

Transfer onion mixture to the bowl with sausage.

Add French bread, cornbread, pine nuts, rubbed sage, poultry seasoning, and salt; stir to combine. Add chicken broth and mozzarella cheese; stir until bread absorbs broth and stuffing is combined.

Transfer stuffing to the prepared baking dish; pack in. Dot butter over top. Cover dish with aluminum foil.

Bake in the preheated oven for 45 minutes; uncover dish and continue baking until top turns golden brown, about 15 minutes more. Sprinkle with fresh sage and shaved Parmesan cheese; serve.