1. Prepare the chicken: Start by patting the chicken cubes dry with paper towels. Season them with a pinch of salt and pepper. Heat the olive oil in a large skillet or Dutch oven over medium-high heat. Once shimmering, add the chicken and cook for 5-7 minutes, stirring occasionally, until browned on all sides and mostly cooked through. Remove the chicken from the skillet and set aside.

2. Saute the aromatics: In the same skillet, add the chopped onion and cook for 3-5 minutes until softened and translucent. Then, add the minced garlic and sliced mushrooms, cooking for another 3-4 minutes until the mushrooms have softened and released their moisture.

3. Build the creamy sauce base: Pour in the chicken broth, scraping up any browned bits from the bottom of the skillet with a wooden spoon. Bring the broth to a simmer, then stir in the heavy cream, softened cream cheese, Italian seasoning, salt, and pepper. Whisk continuously until the cream cheese is fully melted and the sauce is smooth and creamy.

4. Incorporate the greens: Reduce the heat to medium-low. Add the fresh spinach to the skillet, stirring gently until it wilts into the sauce, which usually takes about 2-3 minutes.

5. Combine and finish: Return the cooked chicken to the skillet, stirring to coat it evenly with the creamy sauce. Allow it to simmer gently for another 2-3 minutes, ensuring the chicken is thoroughly heated through and absorbs the flavors of the sauce.

6. Add the cheese and serve: Stir in the grated Parmesan cheese until it’s fully incorporated and melted. Taste and adjust seasonings if necessary. Serve immediately, garnished with a little extra Parmesan cheese if desired.