Wash the potatoes and boil them in boiling water for about 20 minutes until soft. Meanwhile clean the leek, cut it into approx. 0.5 cm thick rings and wash thoroughly. Wash parsley, dab dry and chop the leaves of 4 stems coarsely.
Cabanossi cut into slices. Wash the tomatoes, grate them dry and cut them into small pieces. Drain potatoes, rinse and peel. Heat oil in a large pan. Fry potatoes and leek for about 5 minutes.
Add the cabanossi and sauté. Season with salt and pepper and sprinkle with chopped parsley. Remove the vegetables, cabanossi and potatoes from the pan and keep warm. Add tomato paste and tomato pieces to the pan and sauté for 1-2 minutes.
Deglaze with broth and simmer for 2-3 minutes. Season the sauce with a little sugar, salt and pepper. Add vegetables, cabanossi and potatoes and mix coarsely. Garnish with parsley.