Peel the potatoes and cut into small cubes. Quarter the leek lengthways and cut finely. Peel the onions and also chop them into cubes.
Heat the oil in a large saucepan. Fry the leek and onion well, then add half of the potatoes and continue frying. Then deglaze with the white wine and let it boil down. Pour in the vegetable stock. Add the caraway seeds and let everything simmer for about 30 minutes. Then mix with the hand blender.
Add the remaining potatoes and continue to simmer until they are firm to the bite. Finally season with salt and pepper. Before serving, heat the wieners in the soup.