Sauté the savoy cabbage in butter, season with salt, add caraway seeds, add mashed potatoes, mix well. If too dry, add a little milk. Add parsley and mix.
Layer in a buttered dish: 1st layer of savoy mashed potatoes, 2nd layer of saucisson, 3rd layer of bechamel, 4th layer of remaining savoy mashed potatoes.
Mix parsley, bread crumbs and melted butter in a small baking bowl with a fork until crumbly.
Spread crumble evenly over gratin and gratinate for about twenty min in the middle of oven heated to 220 degrees.