KFC describes its closely guarded original fried chicken recipe as “one of the biggest trade secrets in the world.” The company says the original handwritten recipe is housed in a 770-pound safe encased in two feet of concrete and guarded by video cameras and motion detectors.

It is the Fort Knox of fried chicken.

Despite all that, the recipe for the spice blend used to prepare the chicken may have been accidentally revealed to a reporter for The Chicago Tribune by Joe Ledington, a nephew of the man who made the recipe famous. The newspaper printed the article, along with what might be the recipe, last week.

The reporter, Jay Jones, was sent to Corbin, Ky., to write a story for The Tribune’s travel section about the town where the colonel served his first fried chicken. While there, he arranged a meeting with Mr. Ledington, whose uncle, Col. Harland Sanders, founded Kentucky Fried Chicken and was its snowy-haired ambassador.

Mr. Ledington greeted the reporter with a family scrapbook that he said had belonged to Claudia Ledington, the second wife of Colonel Sanders, who died in 1996. Her last will and testament was stuffed in the back of the scrapbook, and its final pages contained a handwritten recipe for a blend of 11 spices, Mr. Jones said.