Poached Beef Tenderloin
Poaching a tenderloin of beef is the surest way to obtain perfectly and uniformly rare meat. Whether you choose a 2-pound piece, which will easily serve four, or a larger one, the procedure and results are consistently the same, making the dish ideal for dinner parties. As long as the meat is of fairly consistent thickness, every slice you cut —with the exception of the very ends—will look like the others. Buying the beef is simple but usually can be made even simpler with an advance call to the butcher; ask for the thick (châteaubriand) end of the tenderloin, 2 to 3 pounds (he will be willing to cut it to any size you like), in one piece, tied. If you allow the meat to reach room temperature before poaching, cooking time will be reduced by a few minutes; but it will be no longer than 20 and probably shorter anyway.
- One 3-pound piece beef tenderloin from the thick end, preferably at room temperature
-  6 cups beef or chicken stock, preferably homemade , or water
- Salt to taste
-  Garnishes, such as minced shallots, Dijon mustard, chopped cornichons, coarse salt, and salsa