I love just tossing in a frozen chicken or parts, along with whatever vegetables may be available -- put veggies on the bottom and chicken on top if you want more of a roasted chicken since the veggies will keep the chicken out of the liquid that is generated and let it cook all day.
Just make sure any "spare parts" inside the chicken are removed, if they exist, I try to buy them without the innards, but that's not always an option. Seasoning is optional. Use the bones and leftovers later to make soup stock.
Support bacteria. It's the only culture some people have.