Soak beans overnight in cold water, rinse cold and simmer covered with water al dente.
Strain,douse with cold water and drain.
Boil potatoes in salt water. Strain, peel and cool them. Cut the potatoes into 1 cm thick slices. Cut the leek into slices. Cut the meat into 4 equally thick steaks, salt, pepper and coat with oil on both sides. Fry in a pan on both sides.
Peel potatoes in oil golden brown. Add leeks and roast them briefly. Fold in the beans and heat. Season with salt and pepper.