For the Beef Roulade

1. Season with salt and pepper on one side of the loin and spread with mustard. Cut vegetables into thin strips for short cooking. Cut the strip lengthwise into strips. Then place leeks and vegetables on the side of the short loin, which is covered with mustard, and form a roll. Combine the roll with the spatula and brown it in olive oil. Add the thyme, rosemary and quarter-cut shallots, and let it boil for 10 minutes at 75 degrees in the oven.

Celery

1. Peel the celery root and cut into 5 cm pieces. Then blanch in boiling water and quench in cold water. Fry the celery stalks in olive oil, season with salt and pepper. Remove from pan and cut into cubes. Then softly boil in milk with the celery root, remove from the milk and thoroughly purify. If necessary, sift through a sieve with salt and nutmeg and finish with the finely chopped chervil.

Dumpling

1. Hold the marrow under running, cold water for 10 minutes until the marrow becomes completely white. Then heat the marrow to room temperature and beat with a snow beaker until the mass reaches twice the volume. Season with salt and pepper and shape from the mass 20 grams of heavy balls, cold these in the freezer.
2. Cook the potatoes with the dish at 180 degrees for about half an hour in the oven and then cut in half. Use a spoon to hollow out the potatoes and allow them to evaporate briefly. Using a potato press, gently press on a work surface and make a small trough into which the melted butter and the remaining ingredients are gently worked in (not kneading). When the dough is smooth, season with salt and pepper and leave to rest for 5 minutes.
3. Divide the potato dough into 60 gram pieces, roll it lightly and fill with the marrow. Then quickly form a dumpling and boil in salt water for 10 minutes. Then pour it out of the water, drain and roll in brown butter

Dressing

1. Remove the meat from the spit and cut into 3 equal pieces. Place the celery puree in the middle of the dish and arrange the bars in parallel. Place the meat on the celery puree, sprinkle with some beef sauce and place the dumpling next to it. Sprinkle with fresh herbs!