Begin by cooking the penne pasta according to the package instructions. Once cooked, drain in a colander and set aside.
While the pasta is cooking, season the chicken breasts with salt and pepper.
In a large skillet, heat the olive oil over medium-high heat. Once the oil is hot, add the chicken breasts to the skillet and cook for 5-7 minutes per side, or until fully cooked and no longer pink in the center. Remove chicken from the skillet and let it rest for a few minutes before slicing it into bite-sized pieces.
In the same skillet, add minced garlic and sauté for about 1 minute until fragrant.
Pour in the chicken broth and bring it to a simmer. Add the heavy cream, sun-dried tomatoes, dried basil, and dried oregano. Stir well to combine.
Allow the sauce to simmer for about 5 minutes until it thickens slightly.
Add the spinach to the sauce, stirring until it wilts.
Fold the cooked pasta and sliced chicken into the skillet, mixing everything together until well combined. Season with additional salt and pepper if desired.
Serve hot, topped with grated Parmesan cheese, if using.