Preheat your oven to 350°F (175°C) to prepare for baking.
In a pot of boiling salted water, cook the spaghetti or fettuccine according to package instructions until al dente. Drain and set aside to cool slightly.
In a large skillet, heat the olive oil over medium heat. Add the finely chopped onion and sauté for about 3 minutes until it becomes translucent.
Introduce the minced garlic and sliced mushrooms into the skillet. Cook for approximately 5 minutes, stirring occasionally, until the mushrooms become tender and release their moisture.
Sprinkle in the all-purpose flour and stir thoroughly, cooking for an additional minute to ensure the flour is well combined with the vegetables and starts to toast slightly.
Gradually whisk in the chicken broth while continuously stirring to prevent any lumps from forming. Bring the mixture to a gentle simmer, allowing it to thicken.
Incorporate the heavy cream along with the Italian seasoning, salt, and black pepper into the sauce. Continue to cook for 5-7 minutes, stirring occasionally, until the sauce thickens to your desired creamy consistency.
Carefully fold in the shredded chicken, cooked pasta, and frozen peas, ensuring everything is evenly coated in the luscious sauce.
Transfer the creamy chicken and pasta mixture into a greased 9x13 inch baking dish, spreading it out evenly.
If using breadcrumbs, sprinkle them generously over the top to add a delightful crunch to the dish.
Finish by grating an ample layer of Parmesan cheese over the top, providing a rich flavor and golden color as it bakes.
Place the baking dish in the preheated oven and bake for 25-30 minutes, or until the top is golden and bubbly, making your kitchen smell irresistible.
Once finished, remove the dish from the oven and let it cool for a few minutes before serving. This will help in setting the layers.
Notes
Serve hot from the oven, garnished with fresh parsley and extra Parmesan cheese.
Keyword bake, chicken, comfort food, creamy, pasta