Key Lime Pie

This classic pie—featuring that signature Key lime citrus flavor, fluffy whipped cream, and a buttery graham cracker crust—is the one of those special recipes I come back to again and again. Not only is this no-bake dessert packed with just the right amount of tang, it also couldn’t be easier to make (AND to make ahead). Once you make it, you might just find yourself bringing it to all your summer get-togethers, celebrations, and dinner parties. I know I will be!

What People Are Saying:

"The PERFECT key lime pie. The crust is so buttery, and the filling is creamy and just tangy enough. my new go-to recipe!" - noelle777

“Just the right amount of tang indeed. I was delighted at how well balanced all the flavors and textures are: the sweetness balancing the tartness, the crunch of the crust balancing the creaminess of the fruit and topping.” - lagares

What Is Key Lime Pie?

Key lime pie is a tart and creamy custard pie that’s baked then traditionally served chilled, often with lots of whipped cream. Its signature ingredient—Key limes—have a unique sweet-tart flavor that make it stand out among other classic desserts.

Key lime pie is practically synonymous with Florida (and the Florida Keys), but jury’s out on whether it originated from there. What is known is that there were likely a few influences at play that made it the Southern treat we know and love today—the pre-refrigeration lack of fresh milk (hence the use of canned condensed milk), particularly in the hot Florida climate, and the pervasiveness there of Key limes. At some point, some enterprising baker combined the two, and I'm so glad they did!

How to Make Key Lime Pie

INGREDIENTS

• Sweetened condensed milk. This is where this pie gets its just-sweet-enough flavor. Heads up: when you’re shopping for this, look for a can that says either sweetened condensed milk or just condensed milk (they’re the same!). DON’T grab evaporated milk, which is unsweetened (and will be unpleasant here).
• Egg yolks. Once it’s baked, it’s these yolks that help set the pie filling and give it an added layer of richness. Hot tip: save your yolks in the freezer—once you’ve got enough, use them to make macaroons or a whiskey sour.
• Sour cream. Similarly, including sour cream gives this added depth of flavor and a delightful mouthfeel. If you don’t want to include it, you should be able to substitute it with yogurt or an additional egg yolk, but I haven’t tried it. Let me know if you do!
• Key limes. If you’re unfamiliar, Key limes are slightly yellow in color and smaller than average limes. They’re more aromatic and floral than regular limes, and pack a more flavorful punch that’s worth the extra effort. That said, if you really can’t find Key limes, you can use regular limes instead. Whatever limes you use, I highly recommend using fresh. I know—it’s a tad tedious to squeeze the juice out of so many tiny limes, but it will make a difference in creating the freshest, boldest flavor possible. If you’re really in a pinch, you can use bottled Key lime juice, but I still recommend picking up a few to use for the fresh lime zest.
• Graham cracker crust. After all that juicing, you’ll be glad to hear that you’ve got my blessing to use a store-bought graham cracker crust! That said, if you’re looking to truly take this pie to the next level, nothing beats homemade. Simply grind 9 graham crackers in a food processor or crush them in a resealable plastic bag until you have fine crumbs. In a large bowl, combine crushed graham crackers, 5 tablespoons melted butter, 1/4 cup granulated sugar, and a pinch of salt, mixing until mixture is the texture of wet sand. Press into the bottom of an 8" or 9" pie plate and refrigerate until ready to use; there's no need to pre-bake it for this recipe.
• Whipped cream. I love topping my Key lime pies with homemade whipped cream, fresh lime zest, and lime slices for an eye-catching, sweet-sour garnish, but feel free to get creative.

STEP-BY-STEP INSTRUCTIONS

Start by preheating your oven and setting up a rack in the center (rather than too close to either the top or bottom of your oven, where the heat is unevenly distributed). Then get those limes zested and juiced! I like to do this way before I’ve started making my pie filling so I can keep my work space tidy. You’re going to need a LOT of limes, which means a lot of fruit trash, so take my advice and zest and juice them before you get out your bowl and beater. Don’t forget to save some zest and slices for garnish too!

Making your own crust rather than using store-bought? Now’s a great time to assemble that and get it chilling.

Once you’ve got your zest and juice and your pie crust ready to go, you can make your filling. Start by beating together your milk, yolks, and sour cream until smooth, then add your lime zest and juice. You could mix it all together at once, but I found that waiting to add the zest made it much easier to get it smooth.

Once it’s all mixed, pour it into your graham cracker crust and pop it into the oven. Bake your pie until the crust is starting to turn more golden, and the filling just begins to puff. It should still be a little bit jiggly (it will set up more as it cools!).

Let it cool, then here’s the hard part—for the perfect texture, you’re going to want to let it chill and further set up for at least 2 hours. If you’ve got the time, overnight is even better.

Whenever you’re close to ready to serve, make some whipped cream to top your pie by beating cream and sugar together until you get stiff peaks. Check out our homemade whipped cream recipe for even more tips if you need. Top your pie with LOTS of whipped cream like we did in our video above, or a little more restrained like we did in our photos. Garnish with some lime slices or wedges and lime zest, then slice to serve.

Full list of ingredients and directions can be found in the recipe above.

Recipe Tips

• How many Key limes do you need to make Key lime pie? There’s no getting around it, it’s a LOT, like upwards of 25-35 limes. It’s so worth it for their fresh flavor, so plan accordingly and grab extra!
• Should Key lime pie have a whipped cream topping or a meringue topping? Either works! I like mine with a more modern homemade whipped cream, but meringue is more traditional, so go for it if you like. Look to our lemon meringue pie for tips on how to make it.
• Can you use regular limes for Key lime pie? If you really can’t find Key limes, you can try and use regular limes, but the pie won’t have quite the same flavor. One compromise could be to use a combination of fresh limes (for the zest!) and store-bought Key lime juice. If you try this, let me know how it goes in the comments below.

Storage

This pie is a great recipe to make ahead of time due to its need to set in the fridge. Make the pie the day before, then let it sit in the fridge overnight till you're ready to serve; top with whipped cream and enjoy! If you have any leftovers, store them in the refrigerator for around 4-5 days. You can also freeze your Key lime pie (sans whipped topping) for around 3 months.