Wash the potatoes and cook in plenty of boiling water for about 20 minutes. Rinse under cold water, drain and peel. Clean the leek, cut into rings and wash.
Cut the potatoes into slices. Heat the oil in a frying pan. Fry the potatoes for 5-10 minutes while turning. Season with salt and pepper. Remove, keep warm and briefly sauté leek in the frying fat.
Add the cabbage and stew for about 5 minutes. Add potatoes again and fold in.