I went on a work trip to Florida recently, and I spent most of my time working and missing my family. I’d intended to go find the best Cuban sandwich in Florida, but by the last day, I’d only had time to buy one cheap cubano from the cheapest place around.

I was disappointed, to say the least. But this all changed on our last day. We had a flight home late in the afternoon and decided we had time for one thing: get up early to go on a seven hour drive across the ocean.

We barely made it back to the airport on time, but during our trip, I tried the region’s most famous dish: key lime pie. In fact, we stopped by one of the two most famous shops (the one that sells modern pies) and had it two ways: classic, and dipped in chocolate.It changed my life, but we’ll talk about that in a minute.

There’s a region in Florida called The Keys (a derivative of los cayos, which means “the small islands” in Spanish. A series of these “keys” extends southwest of the southernmost tip of the state.

I won’t delve into the regional history of this place too much. I’ll just go as simple as saying it quickly became a point of strategic importance for the U.S. Navy, and in the early 1900’s, one of the biggest and most challenging engineering projects in the world was completed when a railway company built a railroad connecting each of these small islands.

Today, Key West is a thriving tourist destination, known for its beautiful beaches, vibrant arts and culture scene, and rich history. The island’s historic district, including Duval Street, Mallory Square, and the Truman Annex, features many preserved buildings and landmarks from the 19th and early 20th centuries.

It’s also the birthplace of key lime pie.

Key Limes

The key lime is not the same thing as a traditional lime, and no, size is not the only difference.

Size: While traditional limes look like a small, green lemon, key limes are much smaller and perfectly spherical. Additionally, traditional limes are deep green, but key limes grow yellow when they’re ripe. Because of this, key limes are necessarily a bit more expensive. Their small size only yields 2-3 teaspoons of juice, while their larger cousins yield 2-3 tablespoons.

Scent and Flavor: Traditional limes are very tart, and slightly sweeter and more floral than lemons. But key limes take it to a whole new level. They are not incredibly tart, but they’re super floral and aromatic. This makes them a standout favorite in citrus-centric desserts like our summer-loving pie or jam thumbprints.

Freshness: While a traditional lime can last for a month in your fridge, key limes shouldn’t be refrigerated at all, and they go back after just a couple of days. Unfortunately, because they’re such a fresh ingredient, it’s hard to find ripe key limes unless you live near the East coast (and some parts of California). Cue another reason that key limes can get a little expensive.

Origin: Key limes are primarily from—you guessed it—the Keys, as well as several parts of Mexico that grow the fruit year round. Traditional limes are generally Persian or Tahitian, and they ship and store much better than key limes.

This brings us to the key lime pie, an incredibly American little delight.

The Key Lime Pie

The key lime pie is a super soft pie, made by creating a tart mixture of key limes and sweetened condensed milk, topped with meringue or whipped cream, and all on top of a crumb crust (though the original used pastry crust). Let’s break down its components.

Meringue vs Whipped Cream Meringue is much more visually impressive because it holds its shape reliably. While whipped cream tends to bleed and deform, meringue maintains its peaks.

This is actually something useful to keep in mind for different culinary endeavors—my wife used a meringue-based cake frosting for my sister's wedding because she knew it would be sitting outside in the heat. While the buttercream of other cakes would have melted quickly, my wife’s cake stayed firm and delicious.

In any case, people tend to prefer whipped cream because cream is delicious. So you know… I won't fault you either way.

If you need a good meringue recipe, just check out this one we published way back in 2014.

Crumb Crust I used to hate crumb crust until exactly four days before writing this article. I’m from a family that has cared very deeply about pies for five generations, and we never make crumb crust for anything but cheesecake. Whenever I saw a crumb crust, I just saw crushed up graham crackers, which aren’t exactly high-quality food. It was a crust that was only ever mediocre at best and usually just held a mediocre, disappointing filling.

But that all changed when I had a key lime pie right at the source of key lime pies. I finally got it!

What can make a crumb crust really good is when the filling of your pie is exceedingly delicate. Classics like pumpkin, pecan, or my Nana’s apple pie go really well with a robust crust that is flaky, yet firm. But what about a filling that is so gentle that a fork is overkill? Enter the key lime pie. In a pie like this, a crumb crust is perfect, and all that matters is getting the right recipe for it.

On that note, I don’t have a good recipe for crumb crust yet, though I’m sure it’ll involve plenty of butter.

The Filling For lack of a better term, this is essentially a citrusy custard. It’s made with sweetened condensed milk, eggs, and lime juice. It’s a good exercise in simplicity, and a great way to enjoy fresh citrus fruit.

Why I Love This Pie

While a lot of desserts are just a “unique twist on eating too much sugar,” the key lime pie actually has something to say. It’s tart and citrusty, and it makes the most of regional ingredients. It contributes to Florida’s culinary identity. It’s wonderfully American.

From a culinary perspective, a lot of desserts suffer from being too cloying—after just a few bites, you get tired of eating it. Key lime pie doesn’t suffer from this problem. It’s so tart, that every bite feels just as fresh as the last. It’s not just a great sweet snack, it’s also a wonderful palate cleanser.

The key lime pie isn’t something I’d serve to end a big dinner. Rather, it’s a snack I’d enjoy in the middle of a hot day, perhaps during a picnic.

Anyway, we still have some time left in summer. Go forth and eat some pie.