Debone chicken. Set chicken meat aside to use for another purpose. If you are not using vegetable scraps to make your stock, roughly chop vegetables. (i.e., onions, carrots, celery. SEE NOTES)
Put the chicken carcass, skin and all the juices from the rotisserie chicken into a medium stockpot. Add the chopped vegetables or vegetable scraps.Season with Herbs de Provence and (optional) salt.
Add enough water so that it comes to about an inch above the chicken and vegetables. Cover and bring to a boil over MEDIUM-HIGH heat. Reduce heat to LOW, and simmer for 1 hour.Remove from heat and let stand, covered, for at least 1 hour.
Strain through metal colander to remove bones and vegetables. If you’d like to remove the fat from the stock, let your stock cool until the fat settles at the top; or, allow it to chill in the fridge for about an hour, and then skim the fat off the top. Personally, we prefer a more "rustic" stock; however, if you don't want any little bits in your stock, you can also strain it through cheesecloth or a fine-mesh sieve.
At this point, you should have about 2 quarts of chicken stock, give or take.
For a more robust, concentrated chicken stock, return the strained stock to the stockpot. Bring to a boil over medium high heat, and continue to boil uncovered for an additional 30 minutes to one hour, or until it has reduced by half (or more, depending on your preference).
Concentrated Homemade chicken stock is ready for cooking, freezing or canning.
Notes
This recipe will make 2-3 quarts of light stock, or one quart of concentrated stock. To use as a recipe ingredient, dilute with water as needed to achieve the desired stock strength. If you don't have vegetable scraps, you can use:
1 yellow onion, roughly chopped
2 stalks of celery, roughly chopped
2 or 3 carrots, roughly chopped
No need to peel anything: just chop them up and throw them in.