Preheat oven to 225°C. Carefully remove the meat from the bone. Put the bone rack in a roasting pan and place in the oven for about 15 minutes.
Dry the cut piece of meat with kitchen towel or paper. Smoke meat by searing with a gas burner, being sure to sear all sides.
Coarsely crush peppercorns in a mortar. Stir together crushed pepper, salt, thyme and rosemary in a small bowl.
Rub the surface of the meat with oil and pat the meat with the spices.
Put the meat in the oven and set to medium-rare.
Cut loose leaves of cabbage and savoy cabbage from the stalk. Remove centre core of each leaf.
Cut the leaves of the sprouts from their stalks. Place all cabbage leaves on a baking sheet with parchment paper and sprinkle with salt flakes. Place in the oven at 160°C for about 10 minutes.
Dry and place the larger cabbage and savoy cabbage leaves one at a time in a hot non-greased pan and press briefly with a spatula. Only the veins in the cabbage will be seared and slightly blackened.
Melt the butter in a saucepan. When it starts to bubble, pour in the hazelnuts. Wait until it starts to smell like caramel and develops that great sweet taste.
Pour in the soy sauce and remove from the stove. Now the umami butter is finished.
Take the pan that you used to fry the meat. Place it on the stove and deglaze with red wine. Sweat shallots with butter in another pan. Pour the wine over the shallots.
Add chicken stock. Bring to a boil. Lower the heat and reduce by half.
Take out the meat from the oven and place the meat on the bone rack tying it into place on the bone with a piece of string. Leave to rest at room temperature for 1 hour.
Lay out a leaf of the savoy cabbage with the seared side face down on a plate and spoon over butter and hazelnuts. Fold the leaf over on one side towards the middle. Place a cabbage leaf, burnt side up next to it. Place a trimmed and tranched piece of meat on top in the middle, and nappe with red wine sauce. Top with the Brussels sprout leaves and finish with some drops of the hazelnut butter.