This classic, easy, Key Lime Pie recipe is a refreshing treat! Start with a simple homemade graham cracker crust, fill it with a 3-ingredient key lime filling, and top everything off with a sweet, fluffy whipped cream.
This is a simple, refreshing, and timeless dessert. I taste-tested so many variations of this pie before settling on this final recipe, and it’s definitely a keeper! I hope you love it as much as my family does! Be sure to check out the video at the bottom of the recipe for step-by-step instructions.
I get this obnoxious notion in my head once a recipe’s been on my site for too long that I didn’t do it proper justice the first time around. For example, I originally shared this Key Lime Pie recipe over 3 years ago as a gift for my Dad on Father’s Day. I vividly remember laboring over the recipe until I was finally happy with it, and I distinctly recall that it was well-received and promptly devoured.
But when I decided I wanted to make a video and breathe new life to this old Key Lime Pie recipe, I was sure that my original recipe could be improved on. I mean, haven’t I learned so much in the past 3+ years? Surely I could make a better Key Lime Pie, right? And so I tried.
I tried variation after variation, playing with vanilla extract additions, renditions made with sour cream instead of egg yolks, visa versa, and combinations of the two. Cream was added, condensed milk was added in a number of different measurements, and I kept a chart of everything different about each key lime pie.
And then, I made my dad (and at least 5 other members of my immediate family, but it’s my Dad’s favorite dessert so he’s the Key Lime Pie Authority) come over and blind taste-test each one and give me their verdict, voting for what was the ultimate, best Key Lime Pie.
And the winner was….
The very same Key Lime Pie recipe I originally shared over 3 years ago. Yup.
If I had any faith in myself I could have spared my local grocery store well over a gallon of condensed milk and myself hours of time, but here we are back at the beginning and I’m happy to (re-)share the verified best Key Lime Pie recipe with you.
So, What Makes the BEST Key Lime Pie?
This was tough, and everyone has different tastebuds, but my taste-testers and I agreed that the BEST Key Lime Pie would be one that was:
- Definitively tart, without making your mouth totally pucker — you need to be able to eat the whole slice and some pies are so tart I can’t make it past one or two bites!
- Sweet, but in a way that complemented the tartness without overwhelming it.
- Simple to make; why change a good simple classic by complicating it with fancy ingredients or techniques!?
- No frills, no surprise twist, just a comfortingly predictable and classic, crumbly graham cracker crust, a creamy filling with a tart lime bite, and a fluffy, thick, sweet homemade whipped cream topping.
Check, check, check, and check.
What’s in Key Lime Pie?
In addition to the staple graham cracker crust and the (not-so) optional whipped cream, a classic Key Lime Pie has just three ingredients:
- Sweetened condensed milk
- Egg yolks
- Key lime juice
After a lot of experimentation (ahem, see above), I definitely believe that keeping it simple with just these three ingredients is best. I tried versions with vanilla extract (it just detracts from the pure key lime flavor of the pie, don’t do it!) and sour cream (not bad, just simply not as good), but in the end, the classic won.
Can I use Regular Limes in Key Lime Pie?
No. Key limes aren’t just smaller and more obnoxious to squeeze than regular limes, they also have a different acidity and flavor to them. While some people will argue that you can substitute an equal amount of lime juice for key lime juice, I cannot recommend it myself (at least not without further testing, and I’m currently all test-ed out).
I am OK, however, with using bottled key lime juice if you are unable to find fresh key limes in your supermarket. It’s very difficult for me to find fresh key limes where I live and when I do find them they’re usually of questionable quality, so I’ve used the bottled version with success many times — do make sure it’s bottled key lime juice, though!
How to Store Key Lime Pie
This pie will keep in the refrigerator for up to three days, just cover it with plastic wrap or aluminum foil. If you’d like to freeze your pie, wrap it tightly and completely and the pie will keep for up to a month in the freezer.
If using whipped cream topping, do not add this before freezing your pie.
How to Make Key Lime Pie
Recipe video at the bottom of the post! If you enjoy watching my cooking videos, I’d love it if you would consider subscribing to my YouTube channel <3
Key Lime Pie
- 1 1/2 cups graham cracker crumbs (170g)
- 2 Tablespoons granulated sugar
- 1 Tablespoon light brown sugar sugar
- 6 Tablespoons butter melted (85g)
- 2 cups sweetened condensed milk* (475ml)
- 6 large egg yolks
- 2/3 cups key lime juice** (160ml)
- 3/4 cup heavy whipping cream (180g)
- 1/4 cup powdered sugar (30g)
- 1/2 teaspoon vanilla extract
- Preheat oven to 350F (175C).
Graham Cracker Crust
- In a medium-sized bowl, stir together graham cracker crumbs and sugars. Stir in melted butter until well-combined.
- Press crumb mixture into bottom and up the sides of a 9.5" pie pan.
- Set pie crust in the refrigerator to chill while you prepare the key lime pie filling.
- In a large bowl, whisk together condensed milk and egg yolks until well combined.
- Stir in key lime juice and whisk until slightly thickened (about 2 minutes).
- Pour into pie crust and bake on 350F (175C) for 18 minutes.
- Remove from oven and allow to cool completely before transferring to refrigerator.
- Chill overnight or at least 6 hours.
Homemade Whipped Cream Topping***
- Before serving pie, combine heavy cream, powdered sugar and vanilla in a bowl. Use an electric mixer to beat until stiff peaks are achieved (the mixture should have a thick, light, "Cool-Whip" like consistency).
- Pipe or spread over chilled Key Lime Pie. Slice and serve.
Storing and Freezing
- Key Lime Pie will keep up to 3 days in the refrigerator, cover with plastic wrap or foil. If freezing, do not add whipped cream until you are ready to serve. To freeze Key Lime Pie, wrap it tightly and thoroughly with plastic wrap and store in the freezer for up to one month. If thawing the whole pie, return to the refrigerator several hours before serving and allow it to thaw in the refrigerator, if thawing a single slice allow it to thaw in the refrigerator for 45-60 minutes before enjoying.
Since I originally shared this recipe for my dad on Father’s Day, I’m leaving in this photo from the original post — here’s my dad making an embarrassing reference at my wedding.
Recipe originally published 06/22/2015, photos and text updated 08/29/2018. Not the recipe, though, that was evidently just right as written and remains the same, albeit with a few additional (hopefully helpful) notes.