This irresistible and refreshing condensed milk key lime pie is made with a buttery graham cracker crust and smooth, tangy key lime filling. It’s the perfect blend of sweet and tart, and a delicious treat for hot summer days!
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Easy key lime pie with condensed milk
Condensed milk key lime pie is super creamy, yet light and refreshing. The filling tastes divine in a traditional graham cracker crust. Simply perfect for spring and summer, but of course, you can enjoy it all year long.
And can you believe that you only need a total of 6 ingredients to make this authentic key lime pie recipe? Amazing right?! Once you have 2 cans of condensed milk, a pack of graham crackers, and a bunch of key limes, you’re good to go!
And best of all, the recipe is surprisingly quick and easy to make. Pies can be intimidating, even for seasoned bakers, but I promise this easy key lime pie recipe is truly simple. You don’t have to fuss with rolling out a crust or cooking a custard on the stovetop. You’ll love it!
Let’s talk about everything you need for condensed milk key lime pie from start to finish! The ingredient amounts can be found in the printable recipe card. Just scroll to get there!
Graham cracker crust
Classic key lime pie is made with a graham cracker crust. It creates a deliciously crunchy, buttery shell to hold the tangy citrus filling. Here are the 3 ingredients required:
- Graham crackers are crushed to give sweetness and crunch. You can swap in shortbread or digestive biscuits if preferred.
- Sugar: Granulated (white) sugar adds sweetness and protects the crust from getting soggy.
- Melted butter helps to hold the pie crust together. I opted for salted butter, but unsalted butter does the trick too.
Key lime filling
Staying true to traditional recipes, you need only 3 ingredients to make the sumptuous key lime pie filling. The filling is perfectly balanced and oh-so creamy!
- Lime juice + zest: Key limes are best for this bright, tangy citrus pie. Some key lime pie recipes use only lime juice, but I find lime zest boosts the citrus flavor. Plus, the little green specks make the pie so pretty. Feel free to use regular (Persian) limes if you can’t find key limes.
- Sweetened condensed milk compliments the tartness of the limes beautifully and creates a rich, creamy filling. You’ll need two 14-oz cans.
- Egg yolks: 4 large egg yolks provide stability + structure and add a hint of color to the lime pie filling.
I like to keep the garnishes simple to let the lime aroma shine. Whipped cream, thin lime slices, lime zest, and graham cracker crumbs are perfect decorations. It tastes delicious and makes for a pretty presentation!
To make a key lime pie that looks exactly like mine, transfer the whipped cream into a disposable piping bag fitted with a large open star tip (I used an M1 tip). Then pipe cream tuffs around the border of the pie.
You could also completely cover the top of your sweetened condensed milk key lime pie with whipped cream or simply dollop it on.
How to make condensed milk key lime pie
Once you have your lime zest and juice, everything else pretty much falls into place. It’s time to make some condensed milk key lime pie!
Step 1: Preheat oven
Preheat the oven to 350°F / 180°C / gas mark 4.
Step 2: Form the pie crust.
Add the graham cracker crumbs, sugar, and melted butter to a large mixing bowl. Stir until the crumbs are coated and everything is well combined.
Step 3: Fill pie pan
Pour the mixture into a deep-dish 9-in / 23 cm pie pan. Press the crumb mixture tightly into the bottom and up the sides of the pie dish.
Step 4: Pre-bake the crust
Bake the pie crust for 8 minutes. Set aside, but leave the oven on.
Step 5: Mix the filling
While the crust is baking, prepare the filling by adding the condensed milk, lime juice, lime zest, and egg yolks to a large mixing bowl. Using a whisk or hand mixer, beat together until well combined, for about 2 minutes. Tap the bowl gently against the counter a few times to release air bubbles from the filling. Pour the mixture into the pre-baked pie crust.
Step 6: Bake
Bake the pie for 15 to 18 minutes. You want the pie set around the edges but still slightly jiggly in the center.
Step 7: Cool & refrigerate
Remove the pie from the oven and place it on a wire rack. Let sit at room temperature to cool completely. Once cooled, place the pie in the refrigerator to chill for at least 3 hours or overnight (and up to 3 days).
Step 8: Whip cream
Beat the cold cream and powdered sugar with an electric mixer on high speed for 3 to 4 minutes, or until stiff peaks form.
Step 9: Decorate
Garnish your key lime pie with decorative swirls of whipped cream, lime slices, and a sprinkle of lime zest and Graham cracker crumbs. I used a piping bag fitted with a large star tip. Alternately, spread the whipped cream on top of the pie.
Tip: Dress up the pie prior to serving so the topping looks its best.
Step 10: Serve
Slice and serve. Condensed milk key lime pie is best served chilled. Enjoy!
How do I know when the filling is done?
It’s tricky to tell when key lime with condensed milk is cooked, and it’s easy to overbake it. Bake the pie until the edges are set, but the center still looks slightly jiggly, for about 15 to 20 minutes. It should be firm to the touch, but not completely solid or totally liquid. The filling will continue to solidify as it cools.
Tips for the best key lime pie
I’m going to let you in on a couple of handy tips that apply to this traditional key lime pie recipe. Read through them before getting started.
- Pre-bake the pie crust for 8 to 10 minutes, so it holds up when you pour the filling.
- Watch the baking time: Condensed key lime pie doesn’t need to bake for long and should be ready within 15 to 20 minutes.
- Chill the pie for at least 3 hours. Chilled key lime pie not only tastes better. The chilling time is needed for the filling to fully set up. If you skip it, you’ll end up with a runny pie.
- Leftover egg whites: You can either make a meringue topping for this pie or try my meringue cookies recipe.
In case you’d like to alter something about this simple key lime pie recipe, I’m certainly not one to stop you. Here are a few variations and substitutions you can try:
- Store-bought pie crust: If you’d rather save some time, take a shortcut and buy a pre-made pie crust. Fill and bake the pie as indicated in the recipe instructions.
- Other crumbs: In place of graham crackers, prepare the pie crust with nilla wafers, ginger snaps, shortbread cookies, or golden Oreos. Use the same amount and make the crust as directed.
- Other citrus fruit: Feel free to swap out limes with other citrus fruits such as grapefruits, lemons, or blood oranges.
- Cool whip: Instead of traditional whipped cream, top your pie with cool whip.
- Meringue topping: Beat 2 leftover egg whites and 1/2 cup granulated sugar in a large mixing bowl until glossy peaks form and the sugar has dissolved, for about 5 to 8 minutes. Spread the meringue topping over the chilled pie and toast with a kitchen torch if desired.
How to store condensed milk key lime pie
Sweetened condensed milk key lime pie is considered a custard pie and you should refrigerate it after 2 hours of cooling time. Leave it in the fridge until ready to serve – it tastes delicious cold!
If you plan to serve this key lime ice box pie on a hot day, I recommend freezing it ahead of time. Let it thaw for a few minutes, then slice it up. It doesn’t melt like ice cream, but would turn very soft if left outside on a hot day.
Can you freeze condensed milk key lime pie?
Yes! Baked key lime pie keeps well in the freezer and can be frozen for 2 to 3 months. Let the pie cool completely, then wrap the pie pan in 2 layers of plastic wrap and freeze. Be sure to omit the whipped cream and garnish. It’s best added right before serving.
How to serve frozen key lime pie
To serve and slice key lime pie slightly frozen, wrap the pie pan in a warm, damp kitchen towel. Doing so will release the pie crust from the pie dish. Run a sharp knife under hot water and carefully dry with paper towels. Slice the pie and clean the blade in between cuts for clean slices.
What condensed milk is best for key lime pie?
Not all condensed milks are equal. For key lime pie, you want to use good-quality full-fat condensed milk. My favorite condensed milk brands are Eagle Brand, Nestle/Carnation, and Milk Maid. Low fat condensed milk doesn’t taste as creamy, and the filling might not set up properly.
What’s the difference between key limes and regular limes?
Two types of limes are available: Key limes grown in the Florida Keys and the more common Persian limes. Here’s what you need to know:
- Florida key limes (aka Mexican limes or West Indian limes) tend to be smaller and have a distinct, slightly floral lime flavor that is tart but not too acidic. They contain more seeds and have thinner, yellowish skin than regular limes.
- Persian limes are larger and tarter than their Florida cousins. They have firm, bright green peel and are often seedless. This is the type of lime generally sold in grocery stores.
Cook’s Illustrated compared the flavors of key lime vs. Persian limes and noted that “Key lime juice tasted slightly less tart and bracing than its Persian counterpart.” They even confirmed this with a lab test, which showing that Persian limes have a higher acidity than key limes.
How many limes do you need for key lime pie?
- Key limes: You need approximately 20 to 24 key limes to generate the 1 cup of key lime juice the recipe calls for.
- Persian limes: For 1 cup, squeeze 8 to 10 regular limes.
Can you make key lime pie with regular limes?
Yes, you can substitute key limes with the standard grocery store Persian limes. The key lime pie filling will taste slightly different but still delicious and is totally worth making.
Can you make condensed milk key lime pie with bottled lime juice?
Yes! Nothing beats freshly squeezed lime juice, but if you’d like to save some time and feel free to grab a bottle of key lime juice. I love Nellie & Joe’s key lime juice, which you can find in many grocery stores and on Amazon.
I don’t recommend regular lime juice. It’s okay for drinks, but the flavor doesn’t translate well into desserts.
Just keep in mind that you don’t get the lime zest, which contributes to the flavor and flair of condensed milk key lime pie.
Can I make this pie recipe with lemons?
Yes, you can replace the lime juice and zest with the same amounts of lemon juice and zest. You’ll end up with a creamy, smooth lemon pie. It has the same texture as key lime pie, but a zesty and bright lemon flavor. For more info, check out our condensed milk lemon pie! We also have this beautiful and refreshing grapefruit pie!