1. Heat a 12 in skillet over medium heat and add the butter to melt. Stir to coat the pan.
2. Add the chicken to the skillet and sprinkle with salt and pepper. Cook, stirring often, until chicken is browned (about 5 minutes)
3. Add the onion to the pan and cook 2 more mins, stirring often.
4. Add the pasta and sun-dried tomatoes to the skillet.
5. Pour in the broth and half and half. Stir well to combine.
6. Bring to a boil, cover, and reduce to a simmer.
7. Remove the lid and stir in grated cheese until melted.
8. Stir in the spinach. Remove from heat, cover and let sit for 5 mins to wilt spinach.
9. Stir well before serving.