Wash the cured pork and put it in a large pot with 1 1/2 litres of cold water. Wash the thyme. Wash and quarter the tomato. Peel onion and cut it roughly into pieces. Add the tomato quarters, onion, bay leaf and thyme to the smoked pork loin.
Bring to the boil and simmer covered over a low to medium heat for about 45 minutes. Clean or peel the soup greens, wash and drain. Cut carrots and parsley root into slices, leek into rings.
Dice the celery. After approx. 30 minutes add the soup vegetables to the pork loin and cook with it. Roast the hazelnuts in a pan without fat, take them out immediately and let them cool down. Wash the parsley, shake dry and pluck the leaves from the stalks.
Grind the hazelnuts in the universal chopper. Add parsley and olive oil, puree and gradually add 100-125 ml cold water. Season pesto with salt and pepper. Remove the smoked pork loin from the pot.
Remove meat from the bone, cut into cubes and put back into the pot. Let stew simmer for another 4-5 minutes. Season with salt and pepper, arrange in deep plates and add the pesto.