Put 3 liters of water in a saucepan and add the pearl barley.
Peel the celery and carrots and cut into small cubes. Clean the leek and cut into fine strips. Peel the potatoes and cut into small cubes.
Add the celery, carrots and leek to the pearl barley. Add 2 teaspoons of salt to the cold water. Bring everything to the boil briefly and simmer for approx. 20 minutes until soft. Then add the sausage. After about 10 minutes add the potatoes. Simmer everything together for another 20 minutes. Remove the sausage and cut into bite-sized pieces. Put it back in the soup. Season the soup with salt and a little pepper. If you like, you can spice it up with a little Maggi.
Note: The pearl barley is not rinsed off separately. This is deliberate and has the effect that they slim out easily when cooked and thus make the soup creamy.