Cut the leeks into rings about five mm thick, mix with salt and cook in the steamer basket for about five minutes until al dente.
Preheat the stove to 200 °C. Put the dough with the parchment paper in the baking pan, flatten it a little bit, fold the overhanging edges and press them firmly. Prick the bottom with a fork.
Mix crème fraîche with breadcrumbs and spread on the base. Put the leek on top. Cut the sausages into two cm pieces and put them between the leek with the cut surface facing up. Sprinkle with Gruyère and caraway seeds.
Bake in the lower third of the oven for about 35 minutes.
To serve, cut the sausage into pieces, dress the salad with oil, salt, honey, vinegar and pepper and bring to the table.