Mrs. Fields Cookies. It has become the stuff of urban legend: In the late 1980s, a chain mail started circulating, purporting to contain the secret recipe for Mrs. Fields chocolate chip cookies, purchased for $250. Debbi Fields actually posted a reply in all of her stores: "Mrs. Fields recipe has never been sold. ... Mrs. Fields recipe is a delicious trade secret."
Similar mail schemes have bedeviled Waldorf-Astoria hotel's red velvet cake and Neiman Marcus' own chocolate chip cookies.
Twinkies. As Steve Ettlinger watched his daughters gleefully munch on Hostess Twinkies one day, he decided to read the ingredients. Horrified by the mumbo jumbo he saw on the packaging, he decided to decode the ingredients. The result -- "Twinkie, Deconstructed" -- chronicles Ettlinger's journey to discover the source of every listed ingredient.
According to Ettlinger, Interstate Bakeries Corp., which makes Twinkies, didn't exactly cooperate with his research.
Krispy Kreme Donuts. The Winston-Salem, N.C., doughnut company sued the operators of one of its own stores last year on a claim that they deviated from the top-secret recipe when they ran out of the ingredients. "Only a very limited number of Krispy Kreme employees have access to the recipe," which is kept in a safe at the company's headquarters, the company claimed in its suit.
The famous confectioner got its start in 1937 when Vernon Rudolph bought a secret yeast-raised doughnut recipe from a French chef in New Orleans.
WD-40. What makes the super-lubricant so lubricated? It has long been a closely guarded trade secret. Indeed, the product has never been patented in order to avoid having to completely disclose its ingredients.
Developed in 1953 by Norm Larsen, founder of the Rocket Chemical Co., San Diego, Calif., WD-40 was originally designed to repel water and prevent corrosion. He perfected his secret formula, which is locked away in a bank vault, on his 40th attempt.
Taco Bell's Beef. This is one secret that was never intended to get out. A California woman sued Taco Bell earlier this year, claiming its taco filling is only 35 percent ground beef. The rest, she alleges in her class action suit, consists of edible padding: binders, extenders, preservatives, additives and other non-meat ingredients.
Taco Bell claims its filling is 88 percent ground beef. Even so ... what's the other 12?