Easy Key Lime Pie
Add Preferred SourceKey lime pie is one of those desserts plenty of people keep buying from the store, figuring it’s too fussy to make at home. It’s one of the simplest pies I make from scratch, since the filling comes together in a single bowl and the oven does the rest in about half an hour.
Graham crumbs, sweetened condensed milk, and bottled key lime juice are all long-shelf ingredients, so you’re not hunting down a bag of tiny fresh limes just to put one pie on the table. The one thing I don’t rush is the chill, because that overnight rest is what turns a soft filling into slices you can cut cleanly.
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Why You’ll Love This Recipe
- The filling comes together by hand in one bowl in a few minutes; the only time you need a mixer is at the end, for the whipped cream on top.
- The graham cracker crust bakes for ten minutes before the filling goes in, which keeps it firm instead of going soft under a wet filling.
- Bottled key lime juice works as well as fresh here, so you can make this any time of year without tracking down fresh key limes.
- One pie feeds eight and keeps for several days in the fridge, so a single afternoon covers dessert well past the day you bake it.
- The tang comes from real key lime juice and zest against sweet condensed milk, not from a boxed mix or food coloring.
Ingredients You’ll Need
A few ingredient notes before you start; the printable card below has the full list with quantities.
- Graham cracker crumbs: buy them pre-crushed or crush crackers you already have on hand. A food processor gives the most even texture, which presses into a crust that holds together under the filling.
- Sweetened condensed milk: this is the backbone of the filling and what sets the pie as it bakes and chills. Do not swap in evaporated milk, which is unsweetened and won’t set the same way.
- Key lime juice: bottled key lime juice, such as Nellie & Joe’s, works as well as fresh and saves you juicing a pile of tiny limes.
- Key lime zest: zest the limes before you juice them, since a spent lime is nearly impossible to zest. If you use bottled juice, keep one fresh lime on hand just for the zest, which carries most of the aroma.
- Sour cream: one tablespoon of full-fat sour cream smooths the filling and softens the sharp edge of the lime. It’s a small amount, so use full-fat rather than low-fat for the texture.
- Heavy cream: this is for the whipped topping. Whip it with a little sugar to medium peaks just before you serve.
How to Make Key Lime Pie
A complete printable recipe and the measurements in both US customary and metric are available in the recipe card below.
Bake the crust
Heat the oven to 350°F (175°C). Stir the graham cracker crumbs, sugar, and melted butter together until the crumbs look evenly damp, then press the mixture firmly into a nine-inch tart pan using the flat bottom of a measuring cup.
Set the pan on a baking sheet and bake for ten minutes, then let it cool while you mix the filling. Turn the oven down to 325°F (165°C).
Mix the filling
Whisk the egg yolks, sweetened condensed milk, key lime juice, zest, sour cream, and a pinch of salt in a bowl until smooth. It will be thin and pourable at this stage, which is normal.
Bake the pie
Pour the filling over the cooled crust and bake at 325°F (165°C) for about 20 minutes, until the edges are set and the center still jiggles when you nudge the pan.
Pull it while the middle is a little loose, because it firms up as it cools and chills; leaving it in until the center looks solid will crack the top.
Cool and chill
Cool the pie on a wire rack, and get it into the fridge within two hours rather than leaving it out on the counter longer than that. Chill it overnight.
The long rest is what sets the filling firm enough to slice cleanly, so this is the step not to shortcut.
Whip the cream and serve
Just before serving, whip the heavy cream with the sugar on medium-high for 3 to 4 minutes, until it holds medium peaks.
Spread or pipe it over the chilled pie, and add a little extra lime zest on top if you want the color.
Recipe Notes and Tips
- Zest before you juice. A zested lime still juices fine, but a juiced lime is almost impossible to zest, so always do that step first.
- Warm your knife under hot water and wipe it clean between cuts. A cold knife drags and tears the filling, while a warm one gives you clean slices.
- Grate only the outer green layer of the lime and stop at the white pith underneath, since the pith is where a bitter, sharp flavor comes from.
- You only need the yolks for this filling, so save the three egg whites for scrambled eggs or an omelet instead of tossing them.
Recipe Variations
- Regular Persian limes stand in for key limes with no other change to the recipe. The flavor comes out milder and a little less sharp, and I’ve tested it this way when key limes were nowhere to be found.
- Swap the graham crust for crushed gingersnaps or vanilla wafers, cup for cup, and bake it exactly the same way. I haven’t tested the gingersnap version here, but the crust method is identical, so it’s a low-risk change that tastes a little warmer and spicier.
- Adding a fourth egg yolk gives a firmer, more custard-like set. That shifts the filling ratio and I haven’t tested it in this recipe, so treat it as an experiment rather than a straight swap.
How to Store Leftovers
This pie is built to be made ahead, since it needs an overnight chill anyway. Bake it the day before you want to serve it, keep it covered in the fridge, and add the whipped cream just before it goes to the table so the topping stays fresh.
Cover any leftover pie and keep it in the fridge for three to four days. The filling is made with eggs and dairy, so return it to the fridge within two hours of serving rather than letting it sit out on the counter.
I don’t recommend freezing this one. Official storage guidance advises against freezing custard pies like this, and in practice, the filling weeps and the crust softens once it thaws, so it’s better eaten fresh within 3 to 4 days in the fridge than stored in the freezer.
What to Serve With Key Lime Pie
A slice of key lime pie is rich on its own, so the partners that work best are light ones. Fresh raspberries or blueberries on the plate cut the sweetness and pick up the tartness of the lime. A small scoop of vanilla or coconut ice cream turns it into more of a sundae if you’re feeding a crowd.
For a party spread, pair it with a pot of strong coffee, which balances the sweetness better than serving a second sugary dessert.
FAQs
Most often it either wasn’t chilled long enough or came out of the oven before the edges had set. The filling always looks loose while it’s warm and only firms up after a full overnight chill. If it still won’t set after that, the ratio of juice to condensed milk was probably off.
Yes. Bottled key lime juice, such as Nellie & Joe’s, is what a lot of bakers use and gives a consistent result. Fresh key limes are more work for a flavor difference most people won’t notice once the pie is chilled.
A cracked top almost always means too much time in the oven or an oven running hot. It’s cosmetic rather than a failure, and the whipped cream hides it, so next time just check the pie a few minutes early.
More Dessert Recipes to Make Next
If you’re planning the rest of the menu, here are a few more desserts from the site worth a look.
- Easy Apple Pie is the one I make when the weather cools off and I want a classic baked fruit pie big enough for a crowd.
- Pecan Pie Cobbler gives you pecan pie flavor without rolling out a crust; it bakes into a self-saucing cobbler with a gooey layer underneath.
- Best Peanut Butter Pie pairs a quick baked graham crust with a no-bake, make-ahead filling, so most of it comes together off the heat.
- Rhubarb Crisp hits the same tart note as the lime if you like sharp desserts, and it comes together faster than any pie.
- No-Bake Chocolate Lasagna is the layered, no-bake dessert I bring when I need to feed a big group without much fuss.
Ingredients
For the crust:
- 1 ½ cups graham cracker crumbs
- 2 tablespoons white sugar
- 5 tablespoons unsalted butter melted
For the key lime pie:
- 3 large egg yolks
- 1 ⅓ cups sweetened condensed milk
- ½ cup key lime juice
- 1 tablespoon key lime zest
- 1 tablespoon full-fat sour cream
- Pinch of salt
- 1 cup heavy cream
- 2 tbsp sugar
Video
Instructions
- Preheat the oven to 350°F. In a medium bowl, mix the graham cracker crumbs, sugar, and melted butter with a fork until combined.1 ½ cups graham cracker crumbs, 2 tablespoons white sugar, 5 tablespoons unsalted butter
- Press the mixture into a 9-inch tart pan using a flat-bottomed measuring cup.
- Place the pan on a large baking sheet and bake for 10 minutes. Remove from the oven and let cool slightly.
- Reduce the oven temperature to 325°F.
- In a medium bowl, whisk together the egg yolks, sweetened condensed milk, key lime juice, lime zest, sour cream, and salt until smooth.3 large egg yolks, 1 ⅓ cups sweetened condensed milk, ½ cup key lime juice, 1 tablespoon key lime zest, 1 tablespoon full-fat sour cream, Pinch of salt
- Pour the filling over the cooled crust.
- Bake for 20 minutes, or until the center slightly jiggles and the edges are set.
- In a large bowl, whip the heavy cream and sugar using a handheld or stand mixer fitted with a whisk attachment. Beat on medium-high speed for 3 to 4 minutes, until medium peaks form.1 cup heavy cream, 2 tbsp sugar
- Let the pie cool on a wire rack for 2 hours, then refrigerate overnight to set. Top with whipped cream before serving.
Notes
- Bottled key lime juice, such as Nellie & Joe’s, works in place of fresh.
- Persian limes can replace key limes for a milder, less tart flavor.
- Zest the limes before juicing them.
- Use a food processor for evenly fine graham cracker crumbs.
- Chill the baked pie overnight so it sets firm enough to slice.
- Warm the knife between cuts for clean slices.
- Cover any leftover pie and keep it in the fridge for 3 to 4 days.
