Optional but nice additions: Fresh ginger root; turmeric root, fresh or dried; dried mushrooms, a couple dashes of Tabasco or sriracha .
PLACE all ingredients in the slow cooker. ADD enough water, preferably filtered, to cover everything by 1 inch (about 12-13 cups). COOK for at least 8 to 10 hours on LOW (24 hours for beef bones).
STRAIN the broth thorough a fine mesh strainer and DISCARD all the cooked vegetables, meat and bones.
TASTE the broth and ADD more salt and seasoning as needed to taste. Let COOL. COVER and PLACE in the fridge overnight to chill. The next day, REMOVE the congealed/hardened fat from the top of the broth.
The broth will keep for 3 days in the fridge and 3 months in your freezer.