I usually make chicken stock in a slow cooker (a la Shannon) but a few months ago, I'd seen something online about saving vegetable scraps to make broth and wanted to try it.
Whenever you trim the tips off of carrots or the leaves off of celery or the outer layers off of an onion, you throw them in the freezer -- just make sure they're clean. When you make chicken stock, you just add everything; since it's being strained out anyway, it's not like you'll be eating the veggie parts you didn't want in the first place.
And hey, it works!
This isn't rocket science and you could probably use the scraps in the slow cooker too. But this made the kind of perfectly clear broth that I don't usually get from my crockpot, so I'm writing it down so I don't forget it for next time:
1. Put a lot of water in a pot and set it to boil.
2. Get rid of all the skin from your chicken carcass. This is worth a few extra minutes, because it means there is hardly any gross fat to skim off the top of your broth after it cools.(Leaving a little bit of meat is good, though.)
3. Put the bones and the veggies in the pot, along with some peppercorns and bay leaves and oregano.
4. Bring to a boil and then turn it down to a low simmer for about three hours, with the lid halfway on.
5. Throw it in the fridge overnight, if possible, and skim if necessary.
Make some soup or freeze it, hooray.