Key Lime Pie

With a bright, creamy, sweet, and tart filling, a perfectly crisp graham cracker crust, and a cloud of freshly whipped cream, this easy Key Lime Pie is a true celebration of summer.

I have yet to come across someone that doesn’t salivate at the mere mention of key lime pie—members of my household included. With its creamy, tangy, tropical fresh and bright flavour, it has been charming palates for decades.

The recipe I share with you today includes the familiar, classic ingredients—egg yolks, sweetened condensed milk, lime juice and lime zest—but I’ve also thrown in a bit of yogurt. The yogurt tames the sweetness and the lime’s acidity. The result is a slightly creamier pie that is delightfully sweet with the perfect amount of tartness.

The crispy graham cracker crust, infinitely easier than a pastry crust, is the perfect counterpoint to the creamy sweetness of the filling. A cloud of whipped cream, with just a touch of sugar added and topped with flecks of lime zest, mellows it all out giving you pure sunshine in every bite. It’s no wonder this delightfully refreshing dessert is everyone’s all-time favourite treat.

Why You’ll Love This Recipe

• It’s the perfect summer dessert that everyone seems to love.
• Full of tropical, refreshing flavours.
• The inclusion of yogurt in the filling gives it a silkier, creamier texture.
• It’s incredibly easy to make!
• Electric mixer and food processor are optional; All you need is a whisk.
• Few, easy to find ingredients.
• This is the perfect dessert to make ahead.

Ingredients And Notes

• Graham cracker crumbs: You can use graham crackers that you crush yourself, or store-bought graham cracker crumbs. In a pinch, you can buy a pre-baked crust but I don’t find them as tasty.
• Melted butter and/or coconut oil: I like to use some coconut oil in the crust for a bit more tropical flavour but you can use all butter if you prefer.
• Brown sugar: A bit of sugar in the crust helps it crisp up when baked. You can use just about any sweetener you prefer here but I feel like the bit of caramel flavour in brown sugar works well here.
• Egg yolks: I use 3 egg yolks for the filling which is less than most key lime pies call for but that’s because I also add yogurt to the filling (more on that below). I have seen many recipes for eggless key lime pie that use all yogurt or sour cream. I tested some myself but, ultimately, my expert testers (thank you L + B!) way preferred a filling with the inclusion of some egg yolks.
• Sweetened condensed milk: The thick and creamy mixture of sweetened condensed milk is a key ingredient in a key lime pie. Without it, I’m not sure the filling would set so I can’t offer any substitutions. See section below for the difference between the cans of sweetened condensed milk sold in Canada and the ones in the US.
• Greek yogurt: I’d like to say adding yogurt to the mixture is optional but I urge you to give it a try. A bit of yogurt in the filling softens the sour edge of the limes and keeps it from being overly eggy or sweet. Make sure you use full-fat Greek yogurt. Otherwise the pie will not set. I also use a bit of yogurt in the whipped cream topping. I got that idea from Alison Roman’s Dining In  and I love that it adds a little bit of tanginess but also gives more structure to the topping and helps prevent the whipping cream from “falling” once refrigerated.
• Lime zest: This is a key ingredient in a key lime pie giving the filling more brightness and a lot more flavour. Make sure to always zest the limes before you juice them. Once any citrus has been juiced, it is near impossible to zest it.
• Lime juice: Key lime pies are traditionally made with the juice of key limes, hence the name. I have searched high and low in my area and have not found them so I use Persian limes—aka regular limes you find at any grocery store. For this recipe you will need 3/4 cup lime juice. The amount of limes you need to get 3/4 cup of lime juice will depend on how juicy your limes are. If your limes are juicy and on the larger side, you will need about 6-8 limes. See section below for more on the best lime juice for key lime pie.
• Optional topping: You don’t have to top your key lime pie with anything. But this whipped cream topping made with heavy cream, Greek yogurt, and just a bit of powdered sugar is not only outrageously delicious, it will help mellow out all the sharp tanginess in the filling.

Canadian Sweetened Condensed Milk Vs American

This recipe calls for 14 ounces (397ml) of sweetened condensed milk. The problem is if you’re in Canada, you will notice the cans contain only 300ml which is a pretty significant difference. Because I live in Canada, I tested this recipe using only 300ml of sweetened condensed milk but I found I had to also reduce the lime juice and the yogurt. Ultimately, I preferred the pie with a bit more condensed milk. Apologies to my Canadian readers that will have to buy two cans and use only a third of the second one. But I’m confident once you taste this outstanding key lime pie, you will forgive me twofold :))

Best Lime Juice For Key Lime Pie

Purists look away…regular limes are perfectly fine for a key lime pie. Yes, key limes are a lot more tart than regular limes and some say a bit more floral. But they are really hard to find unless you live in Florida, plus those teeny tiny limes are so fastidious to juice. If they aren’t available where you live, don’t let that stop you from making this pie. Regular limes make a delectable key lime pie.

A lot of people swear by Nellie and Joe’s store bought key lime juice but I have never tried it. In a pinch, I’m sure it would do just fine.

However, I would definitely not recommend using bottled, regular lime juice. Most brands contain sugar and other unpleasant flavours. It doesn’t take much effort to juice a few regular limes and the difference will be noticeable.

How to Make a Graham Cracker Crust

You will need graham cracker crumbs to make the crust for this key lime pie. While a food processor makes quick work of blitzing the crackers, you can also crush them by hand.

1. With a food processor: Break up the graham crackers into pieces and add to the bowl of a food processor. Pulse a few times until they are finely crumbled. To crush by hand: Place half of the graham crackers in a resealable plastic bag. Use a kitchen mallet or rolling pin to crush until fine. Dump the crumbs into a medium bowl and repeat with remaining crackers.
2. Add brown sugar, salt, melted butter, and coconut oil (if using) to the prepared graham cracker crumbs and stir until the mixture resembles wet sand.
3. Transfer mixture to a 9-inch pie plate (see more on which pie plate to use below) and press crumbs firmly into the bottom and up the sides of the dish making an even layer. You can use the bottom of a ½ or 1/2  cup sized dry measuring cup to do this. The more you compact the crust, the better it will hold together.
4. Bake for 10-12 minutes, until the crust is just starting to browned. Remove from the oven and let the crust cool slightly while you prepare the filling.

How to Make Key Lime Pie

The only negative about making this easy key lime pie at home, is it will test your patience. You really must let it chill for at least 3 hours before serving, but 6 or overnight is best.

• Preheat the oven to 350ºF. Prepare and bake the graham cracker crust following instructions above.
• In a large bowl, whisk the egg yolks until pale and creamy, about 2 minutes. Add the sweetened condensed milk and whisk to combine. Using a spatula, stir in the yogurt, lime juice, and lime zest. Pour the mixture into your partially baked crust (it’s ok if it’s still a bit warn) and bake until the filling is set and barely jiggles, about 23 to 25 minutes. It will continue to set as it cools.

• Transfer the pie to a wire rack and let cool to room temperature, about 45 minutes. Place in the refrigerator to chill thoroughly, at least 3 hours, but overnight is best.

• Dollop whipped cream topping and lime zest over pie, if using, and serve immediately.

TIPS AND FAQS

Can I make the crust in advance?

Yes! You can make it a day in advance and chill overnight. Bring to room temperature before pouring in the crust.

Can I make the filling in advance?

The filling can be made in advance and chilled for up to 2 days. I wouldn’t add the filling to the pre-baked crust until ready to bake pot. Otherwise, the crust might get soggy.

Does the pie really need to chill?

It does. Otherwise you will not be able to cut through it without it falling apart. Furthermore, this is a pie that should always be served cold.

Does the filling need lime zest?

The oils in the rind of a lime have strong and aromatic flavours that kick up the citrus taste in this key lime pie. Particularly if you aren’t using key limes, make sure to add lime zest to the filling for best results.

How do I make a lime twist garnish?

Ingredient Substitutions

• Sweetened condensed milk – I have not tried it but some people have had success using coconut sweetened condensed milk. It may not thicken as well as regular condensed milk.
• Egg yolks – You can replace all the egg yolks with 1 cup of yogurt and use two full cans of sweetened milk. This makes a delicious key lime pie, though perhaps it leans a little more towards a cheesecake-like pie.
• Key lime juice – Use regular limes or bottled Key Lime juice. You can even use a combination of lime as lemons.
• Graham crackers – For a gluten-free pie, look for gluten-free graham crackers or use a gluten-free pie crust.
• Greek yogurt –  You can also use sour cream (not low-fat).

To Store

Key lime pie will keep for 3-4 days in the fridge, covered loosely with plastic wrap. I don’t recommend freezing key lime pie.

More Summer Dessert Recipes To Try

• Strawberry Rhubarb Galette
• Peach Crisp 
• Plum Clafoutis
• Strawberry Rhubarb Polenta Crisp

If  you give this Key Lime Pie recipe a try, please feel free to leave a comment and/or a star rating below. We appreciate and welcome all your feedback. Thank you!