Place all the ingredients into a large stockpot and cover with ample water, bring to a boil, then reduce to a low simmer for 4 hours
Skim off any foam that accumulates, but using rotisserie chicken rarely creates a lot of foam
When finished strain through a colander, then use a large glass bowl to press the remaining meat, bones and vegetables to extract as much liquid as possible
Wipe out the pot, then strain the stock back into it with a fine mesh sieve
Strain one last time through a cheesecloth lined sieve back into the bowl and let it cool
Cover tightly and refrigerate. Scrape off any fat that solidifies on top, then store in tightly covered containers for up to a week, or freeze for 2-3 months