Remove outer leaves from cabbage, cut into half, remove the stalk and cut into thin strips. These boil in salted water until al dente, strain and drain.
Peel potatoes and cut into medium-sized cubes. Prepare with butter and flour a light roux, douse with 600 ml of soup and bring to a boil, stirring constantly. Add potato cubes and season with garlic, a pinch of cumin, salt and pepper. Boil potatoes al dente, if necessary still pour soup. Fold in cabbage and warm.
Boil scalded sausage and serve with the potato cabbage.