Creating the Creamy Low Carb Chicken Spinach and Mushroom Bake is easy when you follow these steps:

1. Preheat Oven: Preheat your oven to 375°F (190°C).
2. Sauté Chicken: In a large oven-safe skillet, heat the olive oil over medium heat. Add the cubed chicken and season with salt, pepper, onion powder, and garlic powder. Cook until the chicken is browned, about 5-7 minutes.
3. Add Garlic and Mushrooms: Stir in the minced garlic and sliced mushrooms. Sauté for another 3-4 minutes until the mushrooms are tender.
4. Incorporate Spinach: Add the chopped spinach to the skillet, stirring until wilted, which should take about 1-2 minutes.
5. Create Sauce: Pour in the heavy cream and mix well. Bring the mixture to a simmer, allowing it to thicken slightly.
6. Add Cheeses: Stir in the mozzarella and Parmesan cheeses, reserving a small amount of mozzarella for topping. Mix until the cheese is melted and well combined.
7. Transfer to Oven: If your skillet is oven-safe, sprinkle the reserved mozzarella on top. If not, transfer the mixture to a baking dish and then top with mozzarella.
8. Bake: Place the skillet or baking dish in the preheated oven and bake for 20-25 minutes, or until bubbly and golden brown on top.
9. Serve: Remove from the oven and let cool for a few minutes before serving.

By following these steps, you’ll create a rich and creamy dish that highlights the delightful combination of chicken, spinach, and mushrooms.