Deliciously tart and smooth, this gluten free key lime pie is made with a simple gf graham cracker crust and filled with a rich, classic key lime custard. You won’t believe how quick and easy it is.
What makes this recipe for gluten free key lime pie special?
As a kid, I had the perfect slice of key lime pie while in the Florida Keys. I’ve been chasing that moment ever since. That first creamy-crunchy sweet-n-sour bite, the brightest lime flavor, and that smooth custard.
When I returned to Key West just a few years ago, the pie was just as I’d remembered it. But if I’d had my gluten free son with me, there would have been no safe gluten free key lime pie for him to eat.
If you’re from Key West, or your family is, you may do things a bit differently. I’m always happy to learn from someone who knows more than I do.
What is the difference between key lime pie, and lime pie?
Key limes are a type of lime. Their juice is brighter and more tart than conventional limes. Key lime pie is made with the juice of this tiny, green-yellow citrus.
The recipe for the filling has only 3 main ingredients: lime juice, egg yolks, and sweetened condensed milk. It’s named for Key West, Florida, but the origin story of key lime pie seems to be in dispute.
For every 6 eggs in the recipe I use, below, there’s an entire cup or 8 fluid ounces of juice. The acidity in the juice helps to “cook” the egg yolks, which we finish in the oven for a clean-slicing pie.
Because you need the acidity of the citrus juice, you can’t make this pie without an acidic liquid. But if you can’t find key limes or bottled key lime juice, you can come close to the taste with equal parts fresh lemon juice and fresh conventional lime juice.
Where to find fresh key limes (and how to know they’re authentic)
There are some companies that sell what they call fresh “key limes,” but seem inauthentic to me. Key limes are small, for limes. And they’re not as dark as conventional limes, and they have a yellow-ish cast.
Of course, with any fresh fruits, there can be a lot of variation in color and size. They typically come in a mesh bag, and they’re really quite small.
How to juice them
By the way, have you ever juiced a key lime? They have lots of pits, and their size makes using a juice reamer impractical.
To juice them, slice them in half, and squeeze as hard as you can with your fingers over a bowl. Then strain out the pits and any pulp.
Is Nellie and Joe’s key lime pie juice gluten free? Is Manhattan?
The only 100% certain way to get pure key lime juice is by juicing key limes. But they can be difficult to find, and you need a lot of them to make enough juice for this pie.
The ingredients listed on the bottle of Nellie & Joe’s Key West Lime Juice are: filtered water, Key West lime juice from concentrate, sodium benzoate (preservative), and lime oil. There is no statement on their website about whether the product is officially gluten free.
The ingredients on the bottle of Manhattan key lime juice are: water, key lime concentrate, and less than 1/50 of 1% sodium metabisulfite (preservative). I feel comfortable using either bottled juice based on the ingredient list. Please make whatever decision is appropriate for your family, based on your own risk tolerance.
How to make meringue as a topping
Many Key lime pie recipes call for topping the pie with whipped cream (including the bottle of Nellie & Joe’s Key West lime juice). That’s how I remember it being served whenever I was in Key West.
But there’s a lot of chatter on the web about how the only “right” way to serve Key lime pie is with an Italian meringue topping. Of course, there’s no reason you shouldn’t serve it however you prefer.
If you’re interested in Italian meringue, I’ve linked to two recipes from other sources below. It’s nearly the same as our recipe for homemade marshmallow crème.
To make Italian meringue, you simply cook sugar and water to the “softball stage,” then whip it together with egg whites into stiff (but not dry) peaks. You can then pipe the mixture in mounds and bake it at a very low temperature, or just serve it as is on top of your pie.
If you make baked meringues (which are amazingly delicious, by the way), you can make them weeks ahead of time and store them in a single layer, in a sealed container in the freezer. They will retain their crispness that way.
Either way, don’t top the pie until you’re nearly ready to serve it. The soft meringue will begin to weep, otherwise, and the baked meringues will lose their crispness.
Ingredients and substitutions
The custard in this recipe is naturally gluten free—but has 2 other prominent allergens. Here are my best guesses for what you can try to substitute if you must, and how.
For substitution information regarding the cookie crust, please click over to the gluten free graham cracker crust recipe. There are bake and no bake options, plus “ingredients and substitutions” information, there.
Dairy
You must use sweetened condensed milk in this recipe. You can make a different sort of recipe with the flavors of key lime pie, and without sweetened condensed milk (try our no-bake key lime pie and our gluten free key lime pie bars recipes), but you can also make this recipe dairy-free.
There are companies that actually sell cans of non-dairy sweetened condensed milk, usually made with coconut milk. They’re relatively expensive, but I’m glad they’re an option.
You can also make your own sweetened condensed milk more easily than you might think. That recipe (please click the link in the previous sentence) has instructions for making the milk dairy-free.
Egg yolks
Here’s where my powers fail me. You cannot make this recipe, as is, with anything other than the actual yolks of actual eggs.
If you’re wondering what to do with all those egg whites, after separate the eggs, they’re a good start on the roughly 12 egg whites you need for our gluten free angel food cake recipe.
Gluten Free Key Lime Pie
Ingredients
For the crust
1 3/4 cups (350 g) gluten free graham crackers, crushed into crumbs
8 tablespoons (112 g) unsalted butter, melted
For the filling
1 cup (8 fluid ounces) key lime juice (juice of about 2 pounds key limes) (See Recipe Notes)
6 egg yolks (150 g), at room temperature
2 14-ounce cans sweetened condensed milk
1/8 teaspoon kosher salt
For the meringue (optional)
For soft Italian meringue
For baked Italian meringues
Notes
For the key limes
If you don’t have enough fresh key limes to juice or bottled key lime juice, you can substitute 1/2 cup (4 fluid ounces) freshly squeezed conventional lime juice + 1/2 cup (4 fluid ounces) freshly squeezed lemon juice.
Instructions
Grease well a 9-inch pie plate and set it aside. Preheat your oven to 350°F.
In a medium-sized bowl, place the cookie crumbs and melted butter, and mix until the crumbs are moist and begin to hold together. Scrape the crust into the prepared pie plate.
With plastic over your hand to prevent the crust from sticking, press the crust firmly and evenly over the bottom of the pie plate, and halfway up the sides. Set the pie crust aside.
Make the filling. In a large bowl, place the lime juice, egg yolks, condensed milk and 1/8 teaspoon kosher salt, and beat with a handheld mixer or stand mixer fitted with the whip attachment until smooth.
Pour the filling into the prepared crust. Tap the pie plate flat on the counter a few times to break any air bubbles that have formed.
Place the pie in the center of the preheated oven, and bake for 18 to 22 minutes, or until the filling is mostly set, but jiggles a bit when moved gently from side to side. It’s a controlled shake, not like it’s still liquid. The filling will have darkened in color a bit.
Remove the pie from the oven, and place it on a wire rack. Allow the pie to cool to room temperature.
Cover the cooled pie, still in the pie plate, and place it in the refrigerator and cool at least 2 hours or up to overnight before slicing and serving.
If you are serving with Italian meringue, do not top the pie at all until you’re nearly ready to serve it. The soft meringue will begin to weep, and the baked meringues will lose their crispness after about an hour.
Originally published on the blog in 2011 (!). Images and video all new, recipe modified slightly, text new.
Ada says
I made this for a 4th of July party and it was a huge hit! It was for a crowd, so I make 1.5x the amount and it fit perfectly into a 9×13 pan and was easy to cut into squares to serve more.
Nicole Hunn says
That’s great to know, Ada! Sounds like a great party.
George G says
OK Great! Thanks for the clarification. Key Lime Pie, here I come!
George G says
Hi Nicole,
This has to be my favorite dessert of all time. I’m going to make it as soon as I make the DF S C Milk. The description in the blog says to use coconut milk, but the recipe uses coconut cream. I assume that the cream is the correct ingredient.
Nicole Hunn says
Hi, George, coconut cream is the solid in the can of coconut milk. I mention “made from coconut milk” in reference to the packaged products, which usually state on their labels that they’re “sweetened condensed coconut milk.” I wouldn’t know how they make their product. If you’d like to follow my recipe for homemade sweetened condensed coconut milk, please use the ingredients specified. So there’s no inconsistency.
Steph says
Very delicious!!
Saints and Spinners says
My wheat-free uncle thanks you. You may not hear it directly from him, but I know that once I make this pie, he will quietly kvell. Imagine living in the Keys and having to eschew Key Lime Pie, not out of choice, but of necessity. I’d cry, wouldn’t you? He’s not the crying sort, so I’ll have to get maudlin for him. Except that now I don’t.
xo,
Farida
Nicole says
Hi, Farida,
Then your wheat-free uncle is so very welcome. I don’t want to imagine living in the keys and having to give key lime pie the Heisman! I don’t want to! I don’t want to imagine anyone’s world without key lime pie, much less his. So glad he won’t have to stay pie-less. :)
xoxo Nicole
laura west kong says
Looks fabulous! I love key limes.
Nicole says
Hi, Laura,
If you decide to make it, let me know how it turns out!
xoxo Nicole
Heather says
Making this yummy recipe tomorrow! Thanks for sharing! Can’t wait to taste it!
Nicole says
Hi, Heather,
Let me know how it goes! I’m excited. :)
xoxo Nicole
Linda says
Nikki–You’ve outdone yourself with this key lime pie! Just need to pick up the limes, sweetened condensed milk, and I’m on it! Thanks and have a wonderful Labor Day weekend–do fun stuff!
Nicole says
Hi, Linda,
It’s serious. This pie — it’s serious stuff. So glad you’re going to give it a try. Report back!
We’re going to a friend’s house in the Hamptons this weekend. Should be fun. And freeloading is free! Have a great weekend, Linda.
xoxo Nikki
Robin Rose says
I love key lime pie!!! When I was a child, growing up on a barrier island in SW Florida, my sister and I were saddled with the chore of juicing the key limes that grew in our back yard. Where were the child labor laws back then, lol!!! It was a bear of a chore, but soooo worth it! BTW, it helps if you roll the little buggers (limes, not children!) firmly on the counter before juicing. Your recipe is very similar to my grandmothers, except she topped her pie with meringue made from the egg whites. I’ve been making key lime pie, sans crust, for years now, but I really think I need to try this nilla wafer recipe out. Thanks so much Nicole, and have a great weekend!
Nicole says
Hi, Robin,
That does sound like somewhat cruel and unusual to make kids juice all those tiny little limes. Then again, tiny little fingers could be perfect for tiny little limes. :) And, as you say, the reward was great. I really hope you make key lime pie with crust. You deserve to reclaim that memory. I tried another version this weekend with a chocolate wafer cookie crust and brought it to a friend’s house for dinner. Everyone really seemed to love it, but I prefer it with the nilla wafer crust. The nilla wafers don’t compete with the pie filling at all. Perfect.
I hope you try it, and I hope you will write again and let me know how it turned out!
xoxo Nicole
Stasia Todd says
Like Robin Rose, I lived[still live] in Miami as a child. We had a Key Lime tree in our backyard; Limeade was the only drink I remember as a child in the late 40s- early 50s – no soda pop. But I don’t remember it being a problem to cut and squeeze. My mom made KLPie with a gramham cracker crust, as I did when I got married and moved into a house with a Key Lime tree in the back yard – along with a grapefruit and a Valencia orange and a Mango. The Mango was the first thing we righted after Hurricane Andrew. The citrus trees went with the citrus disease scare a few years back.
Will have to try this recipe; for us in Miami, Key Lime Pie is definitely a year around delight.
Thanks for the lovely site.
Stasia
Nicole says
Hi, Stasia,
I’m so jealous of your key lime tree. I would settle for any fruit-bearing tree in my backyard! Although key lime pie is made traditionally with graham cracker crust, I made it with ‘nilla cookie crust for a few reasons: my recipe for graham crackers is only in my cookbook, but my recipe for ‘nilla wafers is a blog recipe. So using ‘nillas means that I don’t have to leave readers high and dry without all the tools needed to make a recipe right here on the blog. In fact, I have a great recipe for little s’mores sandwiches, and I really need the graham crackers for those, and I’m considering asking the publisher for permission to post the graham cracker recipe. So there’s that, and then — I have had key lime pie with graham cracker crust, and I actually prefer the ‘nilla wafer crust, believe it or not. It seems like just the right complement. Go figure!
So sad that citrus disease took your citrus trees. I hope you enjoy the pie!
xoxo Nicole