Key Lime Pie Recipe

Key lime pie combines a tart, tangy, sweet, and creamy custard all in a beautifully toasted graham cracker crust that will have your guests so impressed!

I don’t know why I had never made key lime pie before! It’s honestly one of my favorite desserts to order at a restaurant. I’m not sure if I was intimidated by the process (which I wasn’t familiar with) or had just overcomplicated it in my head (there’s just something so fancy to me about pie). In any case, I finally tried, and I’m SO glad that I did! This key lime pie recipe has easily become my favorite, go-to dessert based on the simplicity of the assembly process and the perfectly sweet and tart key lime flavor all in the creamiest custard. It also feels like quintessential spring, and I love it! 

Where did key lime pie originate?

There is actually some heated debate about exactly where the key lime pie originated. Some will argue that it originated in Key West, FL in the 1930s. There is also evidence that the Magic Lemon Cream Pie (which is a sweetened condensed milk citrus pie) was developed by the Borden condensed milk company in New York City about a decade before the key lime pie made its way to Florida (where pie makers swapped the lemons for the sweet and tart key limes that are indigenous to the area). Another theory is that the pie was first made by sponge fishermen around Key West in the 1800s. Regardless of where the key lime pie was truly born, it is a staple dessert that can be enjoyed in nearly every restaurant in the Florida Keys. 

What does key lime pie taste like?

Citrusy, sweet, and tart are the three words that come to mind when I think of key lime pie. Traditional key lime pie filling contains key lime juice, sweetened condensed milk, and egg yolks giving it a sweet and slightly bitter flavor. The bitter flavor (which comes from the highly acidic key limes) is balanced by the sweetness in the condensed milk, making for a really sharp, brightly flavored custard. It is truly the perfect marriage of fresh, sweet, and tangy flavors that dance on your taste buds. 

How easy is it to make this recipe for key lime pie?

This recipe comes together SO easily (although juicing the key limes is a slightly tedious process, it’s so worth it!). Once you juice the limes, all you have to do is mix the filling ingredients together, pour over your crust, and bake! That’s it! 

Recipe Ingredients 

Just a few fresh ingredients deliver BIG flavor in this key lime pie. Here’s what you’ll need to make it:

For the crust:

• Graham Crackers – to make the crust, you’ll start with 8 ounces of graham crackers (we use these for gluten free) and…
• Butter – 6 tablespoons of softened butter to hold the graham cracker crumbs together. 

For the filling:

• Egg Yolks – you’ll start your custard with 4 egg yolks to make your custard thick, smooth, and rich. 
• Lime Zest – the zest of one lime really enhances the key lime flavor and brings it to the next level. 
• Condensed Milk – to balance the tart and tangy of the lime juice and zest, you’ll use one 14-ounce can of sweetened condensed milk.
• Key Lime Juice – what would key lime pie be without the lime juice? For this filling, you’ll use ¾ of a cup of fresh lime juice. 

For the whipped cream:

• Heavy Cream – to make your honey-sweetened whipped cream, you’ll need one pint (or 2 cups) of heavy whipping cream.
• Honey – to add sweetness, you’ll use 1½ tablespoons of honey.
• Vanilla Extract – 1 teaspoon of vanilla extract gives a subtle warmth to the whipped cream.

Ingredient Modifications

This pie is classic and does not leave a lot of room for modification, but here are some ways you can change things up:

• Use a homemade pie crust – instead of the graham cracker crust, use a homemade pie crust, like this gluten free one. 
• Sub for key limes – can’t find key limes at the store? You can sub the key lime juice for equal parts lemon juice and lime juice for a similar flavor profile. You can also use the more commonly found Persian limes (they aren’t as acidic or sour, so know that the authentic flavor will be altered). 
• Top it – have fun with the toppings for your key lime pie! A personal favorite of mine is a honey whipped cream, which would also be really tasty spiked with some coconut rum if you are serving solely to adults. Meringue is also a popular choice that makes for a beautiful finish! 

How to Make Key Lime Pie

As promised, this process is super easy for any baking level! Here’s how you’ll make this sweet and tangy key lime pie:

1. Preheat – preheat the oven to 350℉.
2. Make the crust – place your graham crackers in the food processor and pulverize until you have a very fine crumb. Add the butter and pulse until the crust comes together. If you don’t have a food processor, that’s ok! Place your graham crackers in a large ziploc bag, squeeze the air out, seal the bag tight, then use a rolling pin or heavy duty bottle to roll over the graham crackers until they are broken into a fine dust. Then stir in your butter by hand. 
3. Toast the crust (optional) – this crust is delicious as a no-bake crust, but if you want to add an additional depth of flavor, toast the crust in the oven for 10 minutes while you prep your filling. Remove the crust from the oven and let cool before adding your filling.
4. Prep the filling – to make the filling, start by beating the egg yolks and lime zest together in a bowl. Then add the condensed milk and beat to combine. Last, add the lime juice and whisk one final time. 
5. Fill the crust – to your pie pan, pour the filling over the cooled crust.
6. Bake – bake for 10 minutes. 
7. Let cool and chill – remove your pie from the oven and let it cool on the counter (until your pie dish is cool to the touch) before covering and transferring to the fridge to finish setting. 
8. Make the whipped cream – add the heavy cream, honey, and vanilla extract to a stand mixer or large bowl and whip the ingredients until soft peaks form.
9. Serve and enjoy! – add desired garnish (additional lime zest, sliced key limes), top with whipped cream and enjoy! 

How do you know when key lime pie is done baking?

Your key lime pie is done baking when the middle is slightly jiggly and firm. The custard will set more as it cools, but you don’t want it to be liquidy. After 10 minutes of baking, give the pan a gentle shake to see how much jiggle you get in the custard. Bake an additional 2-3 minutes if it is still liquidy. 

Frequently Asked Questions