Cook the Pasta: Bring a large pot of salted water to a boil. Cook the pasta according to package instructions until al dente. Drain and set aside.
Cook the Chicken: In a large skillet over medium heat, add olive oil. Season the chicken with salt, pepper, and Italian seasoning. Cook for about 5-7 minutes until golden brown and fully cooked. Remove from the skillet and set aside.
Make the Sauce: In the same skillet, melt butter and add minced garlic. Sauté for 1-2 minutes until fragrant. Pour in the heavy cream and chicken broth, stirring to combine.
Add the Cheese: Slowly add the grated Parmesan cheese, stirring continuously until melted and smooth. Add red pepper flakes if using.
Combine Everything: Return the cooked chicken to the skillet and stir to coat it with the sauce. Add the cooked pasta and toss everything together. If using spinach or cherry tomatoes, stir them in and cook for another 2 minutes until slightly wilted.
Serve & Enjoy: Garnish with fresh parsley and extra Parmesan cheese if desired. Serve hot and enjoy your creamy, garlicky pasta!