Potato salad - Bühl is cooking

Today we cooked a typical german meal for all of us: Kartoffelsalat (potato salad)
For our potato salad you need: 1kg Potato
                                                  1 Onion
                                                  parsley
                                                  salt
                                                  peper
                                                  oil (best out of sunflower)
                                                  vinegar (best out of apple or grapes)
                                                  vegetable stock
                                                 
           for the vegetable stock: 1 karot
                                                 1 piece celaric
                                                    parsley     
                                                    salt
                                                    onion

First you wash and cut all ingredient for the vegetable stock, do them in a pot with water and salt and let it boil 1 hour or more.
After this you wash and cook the potatos. You coult try if they are ready, you have to stick a knife in the potato. If the potato come undown the knife easilly, they are ready. Take the potatos out of the water and peel them. Attention of your fingers, they are really hot. Chip them.
The next stepp is to peel the onion and cut it in little pieces. Sear them in oil.
Do the potato and the onion together in a dish and flavor them with vinegar, salt, peper and vegetable stock. It could look like a soup, that is ok. Because it have to stay 30 minutes till a day till you eat it. With the time it get better. Befor eating try the salad an if it is necessary flavor it again.