Cut the beef into large pieces of 50 g each. For the marinade, mix the finely chopped vegetables with the wine. Dice the meat in the marinade form, cover with cling film and leave to cool for one night.
The next day, remove the meat from the marinade and dry it.
Heat clarified butter in an oven-proof saucepan and sear all the meat cubes all over (about 10 min). Dust with flour and fry briefly. Season with salt and pepper.
Clean mushrooms, remove stems and set aside for the sauce. Cut larger heads into quarters. Pour the marinade, put in the veal slices, add the mushroom stems and the herb bunches and let them bubble. If necessary, pour a little water so that the meat is covered. Steam the meat in the covered saucepan in the heated stove at 180 degrees for 120 minutes. When the meat is tender, lift it out of the braising liquid and set aside, covered. Strain braising stock and reduce to desired consistency. Return meat pieces to sauce and keep warm.
Heat butter in a frying pan or saucepan, sauté mushrooms over medium heat until golden brown, season with salt and pepper.
Cook the tagliatelle according to the package instructions, drain and transfer to a platter. In a frying pan, cream the butter, stir in breadcrumbs and toast until brown and crisp. Dressing: Serve the breadcrumbs on the spot on d