Place bones in a single layer on a sheet pan. Roast for 30 minutes, then flip bones over and roast for an additional 30 minutes.
Add the roasted bones, chopped vegetables, apple cider vinegar, bay leaf, and peppercorns to a large pot. Add enough water to cover completely and bring to a boil.
Once boiling, reduce heat to low. Let simmer for 12 hours, adding more water as needed to keep ingredients submerged and occasionally
skimming any excess fat from the top using a fine mesh strainer or slotted spoon.
Turn off the stovetop and allow broth to cool slightly before removing large bones and vegetables using a slotted spoon. Then, strain bone broth through a large mesh strainer into a large bowl.
Cool bone broth to room temperature before pouring into glass containers. Let cool in the refrigerator for at least 1 hour.
To serve, skim any condensed fat off the top of the broth and heat to desired temperature.