Place chicken bones, carcass, or pieces in a large pot
Add cold water to cover the chicken
Add onion, carrots, celery, garlic, bay leaves, and peppercorns
Bring to a boil over medium-high heat
Reduce to a low simmer
Skim off any foam or impurities from the surface
Simmer for 1 to 4 hours
Add salt to taste near the end
Remove from heat
Strain the broth through a fine-mesh sieve
Discard solids
Cool the broth
Refrigerate or freeze for storage