In an oven-safe pot, sear desired protein until browned on all sides.
Add onion, garlic, bay leaf, peppercorn, thyme, and red wine.
Cook fortwo minutes and then add the veal or beef stock. Cover with a lid orfoil and put in the oven for 45 minutes to an hour.
Pull out of oven,rest meat on a tray and reduce braising liquid until nape (thick enoughto coat the back of a spoon without running off).
Strain the liquid andwhisk in the butter.
Carmalized Onions & Shiitake Mushrooms
Slice onion and sauté on medium/low heat until caramelized, aboutten minutes. Turn up the heat to a med/high and add the mushrooms.Sauté mushrooms for three minutes.
Serve the sliced tenderloin on caramelized onions and shiitakemushrooms and top with veal or beef demi-glacé.