The Debated Origins Of Florida's Iconic Key Lime Pie

Sweet and tart key lime pie is so iconic of Florida and its key islands that it's been named the state's official pie. There's little doubt as to its traditional ingredients — sweetened condensed milk, egg yolks, and key lime juice — but its origin story still remains unsettled. Questions swirl around — primarily whether it should have a Graham cracker or pastry crust, and if it needs a meringue or whipped cream topping — but the real debate is over who, where, and when the dessert was invented in the first place.

There are two theories that both allege to tell the treat's real history. One is that the confection was created in the mid-1800s by fishermen before it was then refined and popularized by a Key West local. Another version is that it was developed circa 1931 by the Borden Company in New York. Borden's sweetened condensed milk was patented in 1856, but it wasn't until the early 1930s that the pie's first printed recipes began to circulate ... a timeline that gives credence to either claim.

In her book "BraveTart: Iconic American Desserts," author Stella Parks places the beginning of key lime pie squarely in the Borden's test kitchen. One of her arguments is that the pie's no-bake magic requires approximately 30% acidity (as from lemon or lime juice) to cause condensed milk to congeal into a custard-like consistency — a formula Parks believes is more likely to have been discovered by a food scientist than a home cook.

David Sloan published his book, "Key Lime Pie: An Intriguing History of Key West's Native Dessert," as a refutation of "BraveTart." He has been researching the pie's history since 1996 and unearthed a trove of evidence to debunk New York as the pie's birthplace. One such clue is an 1889 recipe for it by the Blackwell family of Key West, which appeared in the Miami Herald in 1939.

According to Sloan, credit for the pie's first rendition goes to the island's sponge fishermen (called 'hookers') from the late 19th century. On the Florida Keys episode of "Gordon Ramsay: Uncharted," Sloan gives the chef a demonstration of how they made it using key lime juice, stale Cuban bread or soda cracker crumbs, sweetened condensed milk, and wild bird's eggs — ingredients which were plentiful, provided nutrition, and prevented food waste. The concoction was left to cook under the sun briefly before eating.

From there, legend has it that the concept was adapted by a woman known as Aunt Sally, who Sloan identified as Sarah Jane Lowe Curry. She was the daughter-in-law of shipping magnate William Curry and worked as a cook at the Curry Mansion. Conveniently, Mr. Curry was the first to bring sweetened condensed milk to the islands as provisions for his ships. Originally a working-class food, Aunt Sally's refined version complete with Graham cracker crust and whipped cream topping was likely key lime pie's first introduction to high society.