Peel the asparagus and potatoes and cut into 2-3cm pieces. Cut off the ends of the asparagus and discard.

Put the asparagus and potato pieces in a saucepan and add the water. The vegetables should just be covered. So a little more or a little less water may be needed.

Bring the saucepan to a boil, add salt, sugar and butter and cook for 7-10 minutes.

Then take out the asparagus tips while they still have a bit of bite. They come back later as a contribution to the soup.

Cook the rest for a few more minutes until they are nice and soft.

Now the soup is finely pureed and briefly boiled again. Season to taste and if you like, you can add some nutmeg and parsley in addition to salt and sugar. If the consistency is too thick, a little water will help. If the soup is too thin, let it simmer a little more, but don't forget to stir.

Finally, arrange in a bowl and add the asparagus tips.