Wash the potatoes and cook for about 20 minutes. Drain, quench briefly, peel and let cool. Wash the cured pork loin. Rub with pepper and thyme. Roast in the preheated oven (electric cooker: 175 °C/circulating air: 150 °C/gas: level 2) for about 45 minutes.
For the sauce, peel, wash and finely dice the carrot. Steam in some boiling salted water for about 3 minutes. Drain. Finely dice the cucumbers. Clean and wash spring onions and cut them into fine rings.
Stir soured milk, salad cream and mustard until smooth. Fold in cucumber, spring onions and carrot. Season remoulade with salt, pepper and cucumber water. Leave to stand for at least 30 minutes. Cut the potatoes into slices.
Peel and halve the onion and cut into fine slices. Heat a large pan without fat. Add potatoes and onions in portions. Sprinkle each with a little oil and fry for approx. 10 minutes, turning the potatoes and onions until golden brown.
Season with salt and pepper. Keep ready fried potatoes warm. Slice the sausage thinly. Serve with remoulade and fried potatoes. Garnish with herbs.