Preheat the smoker to 350 F.
Cut the baguettes into 1 inch cubes and toss the pieces in the melted butter, olive oil, and the ground fennel. Either bake at 425 for 15 minutes or until golden brown or place them on the smoker for added smoke flavor (a 350 this will take 20-25 minutes or so).
Once toasted, place the cubes of bread into a large bowl and set it aside.
In a large skillet (you can use the same skillet you will smoke the stuffing in), cook the ground sausage until fully browned and cooked through.
Add the onion, carrots, celery, mushrooms, and minced garlic. Sauté for 6-7 minutes until cooked and tender. Season with the salt and pepper.
Mix the cooked sausage and veggies in with the toasted bread cubes.
In a small bowl, whisk together the stock, cream, and eggs. Pour over the stuffing mixture in the large bowl and fold or toss by hand until everything is thoroughly mixed and most of the liquid is absorbed into the mixture.
Add everything back into the large skillet and flatten the stuffing so its spread out evenly in the pan.
Place the stuffing onto the smoker over indirect heat and smoked for 30 minutes. After 30 minutes toss the stuffing so that the crispy part on the top is mixed in (this creates a nicer texture throughout). Smoked for an additional 30 minutes or until crispy on top and golden brown.
Let rest 5 minutes and serve!