Wash the pork knuckles and dry with kitchen towel. Mix salt and pepper and rub pork knuckle all over. Heat the oil in pan and brown the pork knuckles all around at medium heat. Add the beef broth and bake in preheated oven on the center rack at 400 F for 1 hour 40 minutes.

Mix beer with 1 tsp salt and baste the knuckles every 15 minutes with this liquid.

Cut the onions in quarters. Wash the celery root and cut into slices about 3/8 inch thick.

After cooking for about 1 hour and ten minutes, with about 30 more minutes of cooking, add the vegetables to the pork knuckles and mix with meat juices. Increase heat to 425 F° 220 C°.

Remove the knuckles and vegetables from the pan, cover and keep warm. Season the sauce with any spices of your choice, or simply with salt, and add cornstarch to taste and desired thickness.

Serve knuckles with vegetables spätzle, sauerkraut and red cabbage.