To flavour the head cheese, I use salt and garlic. By adding crushed garlic just before putting the head cheese into the fridge, the garlic has the most flavour because it is raw. In the old days, the hocks and the head were boiled together in a very large pot outside for a couple of days and the whole process of extracting the meat and skin happened after turning out the pieces onto a huge platter.
One can buy a commercial head cheese in the delicatessen department today. It is not really at all similar to making your own though. Commercial processed meat uses gelatin and not the broth of long cooked body parts with a high percentage of connective tissues. It also does not use what most consider waste, but odd bits of meat not really large enough for a cut.
Some people add vinegar to make a pickled version of the head cheese and others add vinegar when it is served as an option These days, a few cultures still make their version of this, the Ukrainians being one. Only the pork hocks and sometimes the feet are used, boiled for a long time, the meat and skin gleaned off and then included in the broth, which does turn to jelly.
I got two pork heads for free. I froze one whole and used the other and there is enough head cheese for at least 3 meals. Plus, this is delicious and highly nutritious, and the dogs will have the skin, ears and skull to chew on and enjoy as well. Would you like to try some?