About every three months I buy a Select Grade whole beef tenderloin, bring it home, carefully remove the fat and silver skin and then cut it into serving size pieces to be vacuum packed and frozen as dinner for two. 

You have no doubt noticed that the extreme front end of a whole tenderloin is smaller and pointy compared to the larger-diameter butt end.  Cuts from this portion of the tenderloin are referred to as tournedos or tenderloin tips.  They are set aside for old French warhorses such as Tournedos Rossini (with foie gras), Tournedos Colbert (with eggs and mushrooms), as well as today's Shabu Shabu, Beef Tenderloin Tips in Pepper Sauce and beef Stroganoff (with mushrooms, mustard and cream)

Tenderloin tips need only brief but intense exposure to the sauté pan; they should be served rare, even in a sauce.  It borders on the criminal to sauté the hell out of tenderloin tips, or boil them in a stew or grill them skewered until the unblanched onions on the kabob are done. Buy sirloin or round steak for that.  So, while beef Stroganoff may look like a stew—it’s not! 

It is written that cookbooks over 400 pages must have a beef Stroganoff recipe.  All call for nice slices of tender beef, onions or shallots and mushrooms served in a sauce made by reducing beef stock, broth or red wine vinegar.  The sauce is often enriched with veal demi glace.  Mustard or paprika is used and the whole mess is finished with heavy cream, sour cream, crème fraîche or a combination thereof. It's a great dish and not difficult to make. 

The key to rave reviews is in the beef prep, Step 1: sauté the beef tips “to blue.”  That is, one step more rare than “rare.”  That is, each piece seared but warm and raw in the center.

Beef Stroganoff
Yield: 4 servings
See Abbreviations, if needed

·   1 lb        tenderloin tips, boneless sirloin or porterhouse fillets, cut bite size
·   2 oz       butter
·   ¾ C      diced shallots or onion
·   15 oz     beef broth
·   ½ C       red wine vinegar (good quality)
·   1 ½ C    mushrooms sliced or broken up
·   2-3 oz   demi glace (optional)
·   1 ½ T    Dijon mustard
·                 S/P
·   ¼ C       sour cream (or a little more, to taste, but don't drown it)

1.  Season the beef tips with S/P and sauté in butter, remove when seared
     but centers are warm and still raw
2.  Drain the tips (reserve drippings) and set aside in a warm place
3.  In the same pan, sweat finely diced shallots in a little more 
     butter and some S/P
4.  Deglaze the pan with the beef broth and red wine vinegar
5.  Bring to boil and reduce by one third
6.  Sauté the mushrooms in a separate pan and set aside
7.  Lower the heat on the sauce to simmer and add the demi glace
     and drippings
8.  Simmer for about 10 minutes and then add the mustard 
9.  Add the mushrooms
10. Add the sour cream and adjust seasoning
11.  Return the tenderloin tips to the sauce and cook briefly over high heat
       to desired doneness
12.  Serve with egg noodles 
Note:  2+ teaspoons of sweet paprika, added at Step 3, can be substituted 
           for the mustard, if you prefer.