01 -
Microwave the cream cheese for 30 seconds to soften it, or let it sit at room temp for a couple hours. Pat the chicken dry, season it with salt and pepper, and preheat your oven to 350°F, setting the rack towards the upper part.
02 -
Cook the spaghetti in plenty of salted water but stop about 2 minutes shy of the time on the package. Drain once it's ready.
03 -
As the pasta cooks, heat olive oil with 1 tablespoon of butter in a big pot over medium-high. Toss the onion in and stir until it gets lightly golden, roughly 4-5 minutes.
04 -
Add your chicken pieces to the pot and stir them around until almost fully cooked, about 5-6 minutes. Move them to a plate afterward.
05 -
Throw the mushrooms, garlic, the rest of the butter, and the Italian seasoning into the same pot. Stir it all until the mushrooms soften and most of their liquid has disappeared, around 5 minutes.
06 -
Turn the heat to high. Gradually stir in the softened cream cheese (cut into chunks to help it melt), chicken broth, and heavy cream. Mix non-stop for 5 minutes until the sauce is smooth and creamy.
07 -
Turn off the stove. Add back the chicken along with the cooked pasta. Mix well so everything’s nicely coated in sauce.
08 -
Scoop the mixture into a 9x13 dish and spread it evenly. Cover with mozzarella and parmesan. Bake it for 30 minutes uncovered, then switch to broil for a couple of minutes to get the top golden and bubbly. Let it cool for 5 minutes before serving.