Season the chicken pieces with salt and black pepper.
Heat olive oil in a large skillet over medium-high heat.
Add the chicken to the skillet and cook for 5-6 minutes until browned and cooked through. Remove chicken from skillet and set aside.
In the same skillet, add minced garlic and sauté for 1 minute until fragrant.
Pour in chicken broth and heavy cream, stirring to combine.
Add uncooked penne pasta, dried Italian seasoning, and crushed red pepper flakes to the skillet. Stir well.
Bring the mixture to a boil, then reduce heat to medium-low and cover the skillet.
Simmer for 12-15 minutes, stirring occasionally, until the pasta is tender and most of the liquid is absorbed.
Stir in grated Parmesan cheese until melted and the sauce is creamy.
Return the cooked chicken to the skillet along with fresh baby spinach. Stir until the spinach wilts.
Remove from heat and sprinkle chopped fresh parsley on top before serving.