Clean the pork knuckle, put it in a tall saucepan and pour in enough water to completely cover the pork knuckle with water.
Add the cloves, rosemary, marjoram, pepper, salt, vegetable stock, two halves of the onion and the beer to the saucepan. Bring to the boil and simmer over a low heat for 1.5 hours.
Take out of the pot and place in a roaster. Slice the remaining seven onions and place in the roaster. Pour five large soup ladles of the stock into the roaster.
Fry in a preheated oven for 1.5 - 2 hours at approx. 200 degrees (top-bottom heat). The knuckle of pork must be nice and brown.
Pour the meat over the pork knuckle over and over again. If there is not enough brew in the roaster after a while, simply put a couple of ladles from the pan back into the roaster.