Finely chop the pumpernickel and toast it in some butter. Then mix it with the cooked sauerkraut and chill. Trim the corn poulard, halve it lengthwise and flatten it to about 3 mm thick. Season the meat with salt and pepper, fill it with sauerkraut, and roll it up. Secure it with kitchen twine or a roulade needle. Preheat the Retigo combi steamer to 180°C hot air and cook the roulades on a roasting tray for about 10 minutes. Chill the cooked roulades in the blast chiller. Coarsely chop the mushrooms for the ravioli, sauté with the diced shallots in olive oil, seasoning with salt, pepper, and rosemary. Continue to sauté, deglaze with white wine, add sour cream, and let everything simmer for 2-3 minutes. Now bind with breadcrumbs until a slightly firm consistency is achieved. Then chill in the blast chiller. Roll out the pasta dough, fill with the mushroom mixture, and form flat ravioli. Cook the ravioli al dente, briefly toss in liquid butter, and cool. Halve and seed the grapes. Slightly caramelize the sugar with butter in a pan, deglaze with white wine, and add the grapes. Briefly toss everything and then cool. For the Verjus jus, heat a light poultry jus and season with verjus. If necessary, reduce further and bind with starch. For serving, arrange 3-4 ravioli cold on a plate and place the cold halved roulade on top. Now regenerate in the Retigo combi steamer at combi steam 135°C with 35% humidity and 80% fan speed for 6 minutes. In the Retigo Blue Vision, it is best to use the insertion timer. Warm the verjus jus and the grapes. Remove the regenerated plate from the steamer, drizzle with a bit of jus, and garnish with a few grapes and a sprig of rosemary. Instead of ravioli, fine tagliatelle with sautéed wild mushrooms can also be served.