Strip the beef tenderloin from the veins, salt and pepper. Fry in a pan on all sides for 40 seconds and put in the oven at t 180 C for 12 minutes.
Peel potatoes and celery root, cut into thin slices. Pour oil on a baking sheet, lay a layer of potatoes, salt, pepper, put a layer of celery on top. Pour cream on top and sprinkle with grated parmesan, cover with foil, put a heavy press on top and place in the oven at t 180C for 60 minutes.
Rinse the spinach, dry, fry whole in vegetable oil with garlic for 15-20 seconds.
Hazelnuts put in the oven at t 180C for 10 minutes. Peel off the husk and boil in milk for about an hour until the pulp, salt a little, add sugar and beat in a blender.
Mix demi-glace sauce (from beef bones) with teriyaki in a ratio of 1: 1, you should get a sweet-meaty taste.