Cook pasta according to package directions; drain and set aside.

Heat olive oil in a large skillet over medium heat. Add chicken and season with salt and pepper, as desired. Cook for 5-8 minutes, or until no longer pink. Remove chicken from pan and set aside. In the same pan, add garlic and cook for one minute.

Sprinkle flour in the pan and slowly whisk in chicken broth, stirring continuously to avoid lumps. Whisk in milk and bring to a boil to thicken sauce. Once sauce has thickened, add spinach and stir until wilted.

Remove from heat and mix in cooked penne, chicken and parmesan cheese until well combined.