Set pressure cooker to "sear" and add chicken, butter, onions, garlic, and bell pepper. Once all are browned, add chicken stock and heavy cream and let it come to a simmer. Add pasta.
Close and lock the lid and set to multi grain for 5 minutes.
When done, quick release and make sure all pressure is released before opening lid.
Carefully open lid and stir in spinach, Parmesan cheese, and cheddar cheese. Season with salt and pepper. Once sauce has thickened, serve and enjoy.
