1. Start by seasoning the chicken breasts with salt, pepper, and Italian seasoning. In a skillet over medium-high heat, sear each breast in the olive oil until golden brown on both sides. This step not only seals in the juices but also adds a delightful caramelized crust that enhances the overall flavor. Once seared, remove the chicken from the pan and set it aside.

2. In the same pan, melt the butter and add the chopped onion. Sauté the onion until it becomes soft and translucent. Then, toss in the minced garlic and sliced mushrooms, continuing to sauté until the mushrooms are tender and lightly golden.

3. Sprinkle the all-purpose flour over the mushroom mixture and stir to coat. Gradually pour in the chicken broth while continuously stirring to prevent any lumps from forming. Finally, pour in the heavy cream and let the mixture simmer until it thickens slightly. Adjust the seasoning with salt and pepper to taste.

4. Preheat your oven to 375°F. Place the seared chicken breasts in a baking dish. Pour the creamy mushroom sauce over the top, ensuring the chicken is evenly coated. Sprinkle the shredded mozzarella and grated parmesan cheese over the dish.

5. Pop the baking dish into the preheated oven and let the Creamy Chicken and Mushroom Bake work its magic for 20-25 minutes. Keep an eye on it, as you’ll want the cheese to be bubbly and golden brown when it’s ready.

6. Once the bake is done, let it rest for a few minutes before serving. The Creamy Chicken and Mushroom Bake pairs beautifully with steamed rice, buttery noodles, or a crusty loaf of bread to soak up every last bit of that irresistible sauce.