There is a lot of flexibility in making soup stock.  You can use the leftovers from your roasted chicken, soup bones and veggies in almost any combination.  It’s a great way to use up leftovers, veggies that are getting a little wilted and unappealing etc.  Here is a basic recipe to get you started.

1 chicken carcass, or some soup bones or ox tail- depending on if you want chicken or beef broth.
2 whole carrots, scrubbed
2 celery ribs
1-2 onions, cut into quarters
1-2 cloves garlic
any wilted veggies lying in the fridge
1 tsp whole black pepper

Put all of the ingredients in your largest pot and cover with water.  simmer on low for at least 2 hours...preferably 4 hours.  Strain everything out of the broth and refrigerate.  Pick of any meat left on the bones to add to your soup.  When it’s cold the fat will congeal on top and you can scoop it off however I have read lately that there is something in the fat of chicken soup that kills the rhinovirus responsible for colds so maybe the stories of chicken soup are true and maybe you should leave just a little of the fat.  I’ll leave that decision up to you.
Make as much stock as you can so you have it on hand for soups, rice dishes, stews, etc.  I can never keep enough of this around.
Don’t forget to add a little celtic sea salt when you make your soup.  It really improves the flavor and celtic sea salt is loaded with the trace minerals you need to be healthy.