It was while investigating reports of a ghost in the lavish mansion built by William "Bill Money" Curry in 1855 that Sloan encountered the original recipe for Key lime pie. "I heard movement on the floor above," he said, "but what stopped me cold was the recipe I saw in the pantry, the recipe for 'Aunt Sally's Key Lime Pie.'"
Sloan's early pie education came flooding back: "Most sources credit an anonymous 'Aunt Sally' with inventing Key lime pie. Well, it turns out that Aunt Sally was the cook at the Curry Mansion and as soon as I saw that paper, my heart started racing and I started to shake. I knew, I just knew. it was like finding the Golden Fleece, the Holy Grail."
Almost every family in Florida has a recipe for Key lime pie and they all claim it's the only authentic version. The filling is rarely disputed: Everyone agrees that green food coloring is for dry-landers and that a proper version is pale yellow. Rather, most debates revolve around the other two variables, crust and topping.
Battle lines in the crust camp are drawn between traditional pastry crust and graham cracker crust. The topping dissension is equally binary. Some believe that a lime pie can only be considered "Key" if modeling a lofty bonnet of meringue. Others argue that a slice of any self-respecting Key lime pie always sports a rakish dollop of whipped cream, preferably one that falls off to the side á la a French beret.
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"There is no cream in the filling," he said. "There was never any cream. This pie was invented to use condensed milk. William Curry made his fortune in hardware. He provisioned ships. He brought the first condensed milk to the Keys not long after Gail Borden invented it in 1856."
“The Curious Case of Key Lime Pie | Epicurious.com [1]”
Having lived in Florida for thirty-six years, I have learned that Key Lime Pie is pale yellow in color. I did not know that it originally used condensed milk (and it's odd to think that condensed milk [2] has been available for 160 years!). I also did not know that Key limes [3] are yellow, not green.
[1] http://www.epicurious.com/archive/seasonalcooking/winter/key-lime-
[2] https://en.wikipedia.org/wiki/Condensed_milk