Follow these simple steps to create your Chicken, Spinach, and Mushroom Low-Carb Oven Dish:

1. Preheat the Oven: Preheat your oven to 375°F (190°C) to ensure even cooking.
2. Prepare Chicken: Season the chicken breasts with salt, pepper, and Italian seasoning on both sides.
3. Sauté Vegetables: In a skillet, heat olive oil over medium heat. Add minced garlic and sliced mushrooms, and cook for about 5 minutes until softened.
4. Add Spinach: Stir in the fresh spinach and cook until wilted, which usually takes about 2 minutes. Remove from heat.
5. Make Cream Sauce: In a bowl, combine heavy cream with salt and pepper. Set aside.
6. Assemble Dish: In a baking dish, place the seasoned chicken breasts side by side. Top each breast with the sautéed spinach and mushroom mixture, then pour the cream sauce over everything.
7. Add Cheese: Sprinkle shredded mozzarella cheese evenly over the top of the dish.
8. Bake: Place the baking dish in the preheated oven. Bake for 25-30 minutes, or until the chicken is fully cooked and the cheese is melted and bubbly.
9. Check Doneness: Ensure that the chicken reaches an internal temperature of 165°F (75°C).
10. Garnish: Once cooked, remove the dish from the oven and let it rest for a few minutes. If desired, garnish with fresh parsley before serving.