Add all the ingredients into a very large pot, ensuring that the herbs, spices, and all the "small" ingredients are placed beneath the meat. This step is optional but helps make skimming the stock easier.
Slowly bring the pot to a boil, then reduce the heat to the lowest setting—just enough to maintain a very gentle simmer. Avoid cooking over higher heat, as this will make the stock cloudy.
As the stock comes to a boil, use a small sieve to skim off the foam or scum that collects on the surface (optional, but it will make the stock clearer, although it doesn’t affect the flavor).
Simmer the stock for 6 hours or longer (a minimum of 3-4 hours will suffice, but the flavor improves with extended cooking).
Do not add any more salt, it’s better to season the dish you’ll use the stock in later.
Once done, strain the liquid and discard all the vegetables and bones. You can reserve the meat for other dishes. I recommend removing large pieces with kitchen tongs first, then straining the liquid through a fine-mesh strainer.
To quickly cool a pot of stock, fill your sink with ice water (very cold water and ice cubes) and place the pot in the sink, ensuring the water level is below the rim of the pot. This way the whole pot cools really quickly.
Now we need to remove the fat from the stock so it's not too greasy (optional). To do that, it's best to place the pot with stock in the fridge overnight. The fat will solidify into a yellow layer on top, which you can scoop off with a spoon. You can discard the fat or save it for another recipe. The stock will turn into a jelly, which is completely normal. See photos in the body of the post for a reference.
Now the stock is ready to use or you can freeze it for later. I find it helpful to freeze it flat in zip-lock bags in 1-cup and 2-cup portions. I also like to freeze some in an ice cube tray, this makes it easy to add small amounts to sauces.
To freeze the stock, you need to warm it until it returns to a liquid state. It is also possible to freeze and measure out the "jelly" (1 cup of jelly is almost the same as 1 cup of liquid), but the problem is that flavorful particles gather at the bottom of the pot when the stock is undisturbed and chilling. If you freeze the jelly as is, your stock won’t be uniformly flavored. Always chill your stock before freezing, then stir it well and place it in zip-lock bags or containers.