Boil potatoes with the skin on.
Then peel and thinly slice while still warm into a large bowl.
Now heat the soup and immediately add to the potatoes.
Season with vinegar, oil, onions, salt and pepper and stir until it becomes creamy.
Finally, season to taste with mustard and sugar.
Preparation Tip:
Refine your potato salad before serving with fresh herbs, such as chives or parsley. After all, the eye eats with you!