This Homemade Key Lime Pie is made without sweetened condensed milk. This is a stovetop key lime pie filling, made with egg yolks, half and half, and fresh squeezed key lime juice. It’s topped with homemade whipped cream and has a vanilla wafer graham cracker crust.
I’ve been wanting to experiment with Key Lime Pie for a while now. It’s one of those pies you hear a lot about during the summer season, but it’s not nearly as common as a summer peach pie or a lemon meringue. Or, at least it’s not that common where I live.
I’m a sucker for those themed food shows where they focus on one particular food and then showcase a few different places known for their version of that food or dessert. One in particular was focusing on pies, and they showcased a place in Florida (whose name I’m blanking on in this moment) where they sell key lime pie by the slice.
This episode was on quite a few years ago, but ever since I’ve been curious to experiment with key lime pie and find the one recipe I absolutely love (and one that’s worth squeezing an insane amount of teeny key limes—if you know, you know).
Every summer I think I’ll get around to it and I never do, but finally, this summer, I think I’ve perfected my Homemade Key Lime Pie Recipe (and it’s made without sweetened condensed milk!).
Why This Recipe Works (And Is Awesome):
- Crust: Most traditional key lime pies use a graham cracker crust, but for this version, I wanted something a bit sweeter so I use half vanilla wafer cookies and half graham crackers to make a rich, sweet crust.
- Key Lime Filling: This is a stovetop key lime pie filling made with egg yolks, half and half, and cornstarch. It’s a very similar recipe to making a lemon custard or a cream pie. I’ll explain more on why I preferred this method to the sweetened condensed milk method below.
- Whipped Cream: Homemade whipped cream makes everything better. True story.
- Fresh Ingredients: I know it can be difficult to find key limes, but fresh key lime zest and juice does make a huge difference in terms of flavor. However, I will offer some substitutions if you cannot find key limes nearby.
- Size: This is a large, deep dish key lime pie. I love key lime filling, and a lot of pies call for a pretty thin layer of custard, and I really want a custard piled high and deep.
- Almost a No Bake Key Lime Pie: The vanilla wafer graham cracker crust is baked in the oven for about 10 minutes, but that’s the only time you use the oven!
- graham crackers
- vanilla wafers
- unsalted butter
- vanilla extract
- brown sugar
- granulated sugar
- cornstarch: This is used to thicken the key lime custard so it’s silky and smooth yet firm.
- half and half: Half and Half is part whole milk, part cream, hence the name half and half. It creates a rich texture in the custard, but you can use all whole milk if you don’t have half and half.
- egg yolks: Save the egg whites in the fridge for a vanilla cake!
- key lime zest: Zest the key limes first, then juice the key limes.
- vanilla extract
- unsalted butter
- key lime juice
- heavy whipping cream
- powdered sugar
- vanilla extract
- key lime zest (for the topping)
How To Make A Perfect Key Lime Pie Crust:
Traditionally, a key lime pie has a graham cracker crust. The sweetness and slight nuttiness of graham crackers pairs well with the tart key lime custard.
- Food Processor: A food processor is so handy to making a homemade crust of any kind, but especially a cookie or graham cracker crust. It pulses the big graham crackers and wafers into fine crumbs that will stick together nicely.
- If you don’t have a food processor, you can put the wafer cookies and graham crackers into a large ziplock bag and crush them into fine crumbs with a rolling pin.
- Press Firmly: When pressing the crust into your pie plate, make sure you press firmly to ‘pack’ the crumbs into the pie plate. This will help keep the crust from being too crumbly.
- Substitutions: I highly suggest using part vanilla wafers and part graham crackers, but you can use all vanilla wafers or all graham crackers if you prefer.
Do I Have To Bake The Crust? Can I Make This A No Bake Key Lime Pie?
A no bake recipe typically refers to using the oven, which this recipe uses for the crust. However, you don’t have to bake a graham cracker crust in the oven.
- I prefer the flavor of a lightly toasted graham cracker crust. I think it has a richer flavor and sticks together better because the butter and crackers are baked together.
- However, you can skip baking the crust in the oven if you’d prefer.
- Just note that this recipe makes the custard on the stove. Technically a stovetop custard is still a no bake recipe, but there is still heat involved. If you’re looking for no bake—like don’t turn on heat at all because it’s sweltering—this lighter Key Lime Pie might be the next thing to try!
How To Make Stovetop Key Lime Pie Filling:
Making this custard key lime pie filling is very, very simple. It’s extremely similar to how I make my Lemon Meringue Pie, and it makes for a very rich, very silky smooth custard.
- Step 1: In a medium sized saucepan, which together sugar, salt, and cornstarch.
- Step 2: In a separate bowl, whisk egg yolks, half and half, and key lime juice.
- Step 3: Place the saucepan on the stove, and over medium heat, slowly whisk the liquid into the saucepan.
- Step 4: Bring the mixture to a boil (over medium heat), whisking constantly.
- Step 5: Once boiling, cook for 30 seconds to 1 minute, until the mixture has thickened and can coat the back of a spoon (whisking constantly).
- Step 6: Remove from the heat and immediately add in butter, zest, and vanilla and mix.
- Step 7: Transfer custard to a bowl, and place that bowl in a large bowl of ice. Whisk the custard to cool it down. Once cool, pour into the crust. Top with whipped cream and refrigerate 3-4 hours.
- Alternatively, you can pour the filling immediately into the crust, however, you will need to cover the custard with plastic wrap, pressing the plastic wrap onto the custard (this prevents the custard from getting a film on top). Then refrigerate until cool. Then add the whipped cream before serving the pie.
- The whipped cream will melt if you put it on top of the hot custard.
Why Make Key Lime Pie Without Sweetened Condensed Milk?
First of all, I love sweetened condensed milk and I do enjoy a key lime pie made with it so making this key lime pie without sweetened condensed milk has nothing to do with not liking the ingredient. (Check out this Banana Pudding—the sweetened condensed milk makes all the difference in the recipe.)
As I was researching key lime pie and seeing the various different methods in different recipes, I was actually really surprised that the majority of recipes not only used sweetened condensed milk, but a lot didn’t actually call for key lime juice. (I understand key limes can be difficult to find and I will provide some solutions to that problem below.)
I really like a good custard, especially for showcasing tart flavors. I think a custard does a fantastic job balancing the sweet and tart flavors. For me, sweetened condensed milk key lime pies were both too sweet and too tart rather than blending the two together.
As mentioned above, my Lemon Meringue Pie is made with a silky smooth lemon custard that uses egg yolks, half and half, and cornstarch so I really wanted to try that method for this key lime pie.
Making a stovetop key lime custard made for an extremely silky smooth key lime filling that was tart enough to remind you it’s a key lime pie, but sweet enough not to make you wince at said tartness. And, the sweetness is perfectly subtle, not as in your face as sweetened condensed milk.
Let’s Talk About Substitutions:
- Key Limes: Key limes are tiny limes that have a more intense flavor than Persian limes, which are the bigger limes you see at most grocery stores.
- It’s not always easy to find key limes in all areas. Here in California, I tend to find them in July and August in certain grocery stores, but not always.
- So, if you cannot find key limes, you can substitute with Persian limes. However, the flavor will differ. It will be a little less intense (key limes have a very intense flavor), and a little less tart.
- You can also use bottled key lime juice and then the zest of Persian limes.
- Half & Half: As explained above, this is a key lime pie made without sweetened condensed milk because we make a key lime custard on the stove using half & half.
- Half & Half is thick and rich, but if you don’t have that on hand, you can use whole milk. Half & Half is half whole milk half heavy cream, so you can also make your own half & half if you prefer.
- This pie does need to be refrigerated before being served. I actually think the pie gets even better after having sat overnight in the fridge so you can definitely make this the night before you plan to serve. Leftovers need to be refrigerate as well.
- There are two methods to cooling down the custard. One includes whisking over ice, which allows you to add the whipped cream on top right away and then refrigerate. The other method includes refrigerating the custard to cool it down, which means having to make and add the whipped cream separately.
- If you do the second method, you will have to refrigerate to cool down the custard, then add the whipped cream, then refrigerate again until ready to serve.
Final Baking Tips And Tricks
- Custard: You are making a custard key lime pie so you will be using egg yolks, cornstarch, and half & half. Use the extra egg whites to make cake!
- Crust: This is a deep dish pie so you need a deep dish pie plate (9” or 10”) so you need to make a homemade crust out of graham crackers and vanilla wafers. A storebought graham cracker crust will be too small.
- Key Limes: Freshly squeezed key limes make the best filling, and it takes about 30-35 key limes to get enough juice. Zest the limes first! Then squeeze out the juice. When zesting, only get the green zest. If you get any white part of the lime, it’ll be very bitter.
- Tartness: If you want the pie to be a bit less tart, you can reduce the key lime juice and reduce the cornstarch. I’ll provide details in the recipe.
Other Recipes To Try Next:
Summer in a slice.
- 1 1/4 cup graham cracker crumbs (about 10 graham cracker sheets)
- 1 1/4 cups vanilla wafer crumbs (about 30 cookies)
- 10 Tbsp unsalted butter, melted
- 1/2 tsp vanilla extract
- 1/4 tsp salt
- 2 Tbsp brown sugar
- 1 1/3 cups granulated sugar
- 6 Tbsp cornstarch
- 1/4 tsp salt
- 2 cups half & half
- 4 egg yolks
- 2/3 cup key lime juice
- 2 tsp key lime zest
- 3/4 tsp vanilla extract
- 2 1/2 Tbsp unsalted butter
- 1 1/2 cups heavy whipping cream
- 3/4 cup powdered sugar
- 1 1/2 tsp vanilla extract
- key lime zest (optional)
- Preheat oven to 350 degrees.
- Using a food processor, mix graham crackers and vanilla wafers, pulsing until they reach fine crumbs. Add in melted butter, salt, vanilla extract, and brown sugar, and mix until combined.
- Pour the crust into a deep dish 9” or 10” pie plate and press into an even layer.
- Bake for 10 minutes.
- Whisk granulated sugar, salt, and cornstarch together in a medium sized saucepan. Set aside.
- Whisk egg yolks, half & half, and key lime juice together in a separate bowl.
- Over medium heat, whisk the liquid into the saucepan.
- Bring the mixture to a boil over medium heat, whisking constantly.
- Once boiling, cook the mixture for 30 seconds to 1 minute (whisking constantly), until the custard has thickened and coats the back of a spoon (mine took roughly 45 seconds, then it was done).
- Remove from heat and add unsalted butter, key lime zest, and vanilla extract. Whisk until combined.
- Transfer the custard to a bowl. Place the bowl with the custard in a larger bowl that has been filled with ice. Whisk the custard to cool it down.* (See notes for an alternative method.)
- Once cool, pour the custard over the crust and smooth it into an even layer. Set aside.
- Whisk heavy whipping cream with a standing mixer or a hand mixer (using the whisk attachments) until soft peaks form. Add in powdered sugar and vanilla extract. Continue whisking until stiff peaks form, or it has reached your desired whipped cream consistency.
- Spread the whipped cream on top of the custard (you can also pipe the whipped cream on top).
- Sprinkle extra key lime zest, if desired.
- Cover and refrigerate at least 3-4 hours before serving (I suggest refrigerating overnight if possible—the pie is more flavorful as it sits).
- Slice and serve.
*Instead of using an ice bath, you can pour the hot custard directly into the crust and spread in an even layer. Place plastic wrap directly onto the custard (this prevents the custard from getting a thin film on top as it cools) and refrigerate. Once cool, add the whipped cream on top. Refrigerate until ready to serve.
**Lime Zest: Zest the key limes before squeezing the juice out. Additionally, only zest the green part of the lime. If you zest too much and start zesting the white part of the lime, it will make the zest very bitter.
***If you cannot find key limes, you can use persian limes (the larger limes in most grocery stores). Or, you can use persian lime zest and bottled key lime juice.
Here are some other summer recipes to try next: