Cook the potatoes with their peel until soft for about 15-20 minutes.
In the meantime, clean, wash and spin dry the lamb`s lettuce. Roast the pine nuts in a pan until golden brown. Peel and halve the onions and cut into thin slices. Bring the vegetable stock to the boil and season with vinegar, salt, pepper, a pinch of sugar and oil. Peel the potatoes, add them to the stock and mash them with a fork. Then stir with a whisk until smooth.
Arrange the salad with the smoked meat, onions and pine nuts on plates and drizzle with the sauce. Serve immediately.