Peel, wash and roughly chop the carrots and celery. Peel and halve shallots and garlic. Wash the rosemary. Wash the lamb knuckles, dab dry and season with salt and pepper.
Heat 2 tablespoons of oil in a large frying pan. Sauté the knuckles in it all around at high heat. Take them out. Sauté the carrots, celery, shallots and garlic in the frying fat. Briefly sauté the tomato paste.
Deglaze with red wine and lamb stock. Add knuckle of pork, rosemary and laurel. Cover and stew for about 2 hours.
Peel and wash the potatoes. Depending on the size, halve lengthwise or cut into pieces. Fry in 2 tablespoons of hot oil all around for about 30 minutes until golden brown. Season with salt and pepper.
Remove the knuckles. Pour gravy through a fine sieve into a pot and let it boil down for about 10 minutes. Put the vegetables with the knuckles back into the roaster and keep covered and warm.
Stir cold butter into the gravy in small pieces one by one until the sauce has a binding effect. Season to taste with salt and pepper. Arrange knuckles with vegetables with potatoes and sauce.
Drink tip: strong red wine, e.g. a Bordeaux.