"Butter Pecan" mystery (1949)

[Bapopik at AOL.COM]

   There's a "butter pecan" mystery that's far, far greater than "pecan pie."
   I found a 1949 cite yesterday, but it's temporarily lost.  There are over 10,000 "butter pecan" web hits.
   "Butter Pecan" is not in Mariani's ENCYCLOPEDIA OF AMERICAN FOOD & DRINK, not in OED, not in M-W, not before 1951 in OCLC WorldCat, not in American Memory, not in Periodicals Contents Index, only four piddly hits on the U.S. Patent & Trademark Office online site...
   Does OED have any files?  Barnhardt?