Put all the chicken bones in an oven tray and cook at around 200C until they are golden brown, moving them during the cooking process so that every part gets grilled.
Remove the excess fat from the oven tray and add water to the tray, then scratch everything out and set it aside.
Grill all the vegetables in a big pan, then add the aromatics (pepper, herbs) and deglaze with half a bottle of red wine. Let the wine reduce until almost dry.
Add the bones and the chicken jus extracted from the tray, then add water to cover the chicken bones.
Add ice cubes (optional) to help with the separation of the fat.
Bring to a boil, then put on low heat (simmering) for about 15 minutes, skimming the foam that forms.
You can add a pork foot at this stage (optional) to add collagen to the broth.
Put everything in the oven at 100 degrees overnight (between 6-12 hours).
Strain everything, remove the broth to a smaller pot, and let it cool down.
Once cooled down, put it in the fridge until cold.
Remove the excess fat on top and reduce the broth, while skimming, until you get the desired texture.