Add chicken to a large stockpot (at least 6 quarts). Wash and roughly chop vegetables (no need to peel) and add to the pot. Add herbs, salt, and peppercorns. Add enough water to cover chicken and vegetables, about 12 cups.
Cover, set over high heat, and bring to a boil. This can take as long as 20 minutes, depending on your stove efficiency.
Once boiling, reduce heat to low and simmer for 2 to 3 hours, or longer as desired.
Turn off heat and let cool slightly. Strain stock into containers, or strain into a large bowl and portion from there.
Let cool to room temperature, then store in the refrigerator for up to 4 days or freezer for 6 months, until ready to use.
Notes
If freezing, make sure to leave 2 inches of headspace in containers to allow for expansion and prevent containers from cracking.