National Key Lime Pie Day

The story

Key lime pie is a tart, creamy dessert from the Florida Keys made with the juice of small, aromatic Key limes, sweetened condensed milk, and egg yolks in a graham cracker or pastry crust. Key limes, also called Mexican or West Indian limes, are smaller, rounder, and more acidic than the common Persian lime, with a floral flavor and yellowish juice.

The pie likely dates to the late 1800s, when Key West had no refrigeration or fresh milk. Canned sweetened condensed milk, introduced by Gail Borden in 1856, kept well in the tropical heat. When mixed with lime juice, its proteins thicken naturally, so early versions may not have been baked at all. Local legend credits a cook known as "Aunt Sally" with the first pie, though some historians point instead to a recipe printed by Borden's company.

Florida is proud of its dessert. In 2006, the state legislature named Key lime pie the official state pie. Purists insist the filling should be pale yellow, never green, and argue over whether to top it with meringue or whipped cream.

On National Key Lime Pie Day, bake one at home with fresh Key limes or order a slice and enjoy a taste of the Florida Keys.