Page 97 - United States of Pie

Key Lime Pie

This pie is the happy result of making do. Life in the Florida Keys
is steamy and tropical—not the ideal climate for cows. So, long ago,
before interstate highways and refrigerated shipping, Floridians had
to rely on condensed milk because fresh milk was rarely available.
Not exactly what most would want to top their morning cereal with,

but it makes a mighty fine pie. Key limes, which were first introduced
to Florida by Spanish colonists in the 1500s, grew throughout the
Florida Keys until a hurricane destroyed many of the groves in 1926.
Nowadays, when you find Key limes at the market, they more than
likely come from Mexico.
To bake or not to bake? That is the question for true Key lime pie
aficionados. When lime juice and condensed milk mix, a chemical

reaction called souring occurs. Souring thickens the filling
substantially, so baking is not required. But because the custard
contains egg yolks, I briefly cook it in order to eliminate any hazard
of food-borne illness (it also ensures a buoyant filling).
If you can’t find Key limes at the market, go ahead and makes this
pie anyway. It will still be delicious—even if it is only a lime pie!

1 Graham Cracker Crust
For the filling

3 large egg yolks
One 14-ounce can sweetened condensed milk
Pinch of kosher salt
½ cup Key lime juice (from 10 to 12 Key limes)
2 teaspoons grated Key lime zest (from 6 to 8 Key limes)

For the topping