The turkey, spinach and white bean soup I made today went over very well with both DH and DSD.
I'm pretty sure this would be good made vegetarian if you added an extra can of beans or so and used veggie broth.
I'm not great at writing recipes, since I improvise a lot to use up leftovers, but here goes.
Add to slow cooker:
6 cups broth (chicken, turkey, veggie)
1 red onion, chopped
1 yellow onion, chopped
2 ribs celery, chopped
handful of baby carrots, chopped
1 can of white beans, rinsed and drained
2-3 cups cooked chopped turkey or chicken
herbs and spices as you wish (I used black pepper, chervil, ground savory, tiny bit of cayenne and two bay leaves)
Cook on low until veggies are soft and cooked through. About 2-3 hours before serving, add roughly chopped fresh spinach - I used about half a bag that I had leftover.