Can this recipe be made ahead or in a slow cooker? How? http://damndelicious.net/2014/12/31/lemon-butter-chicken/?m

I'd probably wait to add the cream and spinach until the last 30 minutes or so. Slow cookers retain much more moisture than dry heat cooking methods, and you're going to get a lot of moisture from the fresh spinach. So, I'd consider skipping the chicken broth, and just letting the chicken cook in its own juices. It really just depends on how much "sauce" you want.