To a 4- to 6-quart slow cooker, add cubed chicken breast, broth, sun-dried tomatoes, and garlic powder. Cover and cook on LOW for 2–3 hours.
Stir in heavy cream and orzo. Cover and cook on LOW for another 30–45 minutes, or until orzo is tender and al dente.
Stir in fresh spinach and Parmesan cheese. Cover and cook on LOW for another 5–10 minutes until the spinach wilts and the cheese melts.
If the sauce is too thick, add a splash of chicken broth to reach your perfect consistency.
Season with salt and pepper to taste. Serve hot, topped with fresh basil and extra Parmesan if desired.