01 - Season the chicken pieces with salt, pepper, and Italian seasoning, ensuring even coating on all sides.
02 - Heat olive oil and butter in a large, deep skillet over medium-high heat. Add chicken and cook until lightly browned and cooked through, about 5-6 minutes. Remove chicken from the pan and set aside.
03 - In the same pan, add onion and sauté for 2-3 minutes until softened. Add garlic and cook for 30 seconds until fragrant.
04 - Stir in the red bell pepper and cook for another 2 minutes until slightly tender.
05 - Add uncooked pasta to the pan, followed by chicken broth and heavy cream. Stir to combine, scraping any browned bits from the bottom of the pan.
06 - Bring to a gentle simmer. Cover and cook for 10-12 minutes, stirring occasionally, until the pasta is al dente and most of the liquid is absorbed.
07 - Return the cooked chicken to the pan, add baby spinach, and stir in Parmesan cheese. Cook for 2-3 minutes until the spinach wilts and the sauce thickens. Taste and adjust seasoning if needed.
08 - Serve hot, garnished with chopped parsley and extra Parmesan if desired.