This irresistible Key Lime Meringue Pie is layers of graham cracker crust, key lime filling, and an Italian meringue. It’s sweet, salty, crunchy, citrusy, buttery, creamy, velvety, toasty, and tangy all in one bite!
A must-make pie during the spring and summer months.
Looking for more lime recipes? Try this Cilantro Lime Pasta, Jalapeno Margarita Mocktail, or these Watermelon Lime Slushies!
Let’s be real – Key Lime Meringue Pie is my ultimate weakness. I’ve tasted many key lime pies over the years, but this recipe… it’s the one that will make you forget about all the others. Most key lime pies are pretty basic: a graham cracker crust, some lime filling, and a dollop or two of whipped cream. But this pie is different.
Mine still has the graham cracker crust and key lime filling, but the game-changer here is the velvety Italian meringue. I personally am a meringue aficionado. I have spent years perfecting my recipe and now I slip it into desserts whenever I can.
Most people hear “Italian meringue” and think it’s way too complicated to make at home. Spoiler alert: it’s not! This topping turns a simple pie into something pretty spectacular… and luxurious! You’ll surprise yourself and your guests with this pie.
If you like meringue pies, you might want to try my Mini Lemon Meringue Pies. They’re cute, citrusy, and the perfect addition to a meringue pie dessert table (along with this key lime pie). And if you prefer a traditional crust, use my Vodka Pie Crust recipe.
Key Lime Meringue Pie Ingredients
Here’s everything you will need to make the graham cracker crust, key lime filling, and meringue topping. Keep reading because there are a few important notes that will make your pie all the more successful.
- Key Limes: Freshly squeezed juice tastes best and you’ll need 1 bag of them. Some recipes call for bottled juice but I beg you, DO NOT use bottled key lime juice. Also, zest a few of the key limes before you juice them because it makes a beautiful pop of color garnish.
- Sweetened Condensed Milk: This is often confused with evaporated milk, so make sure you’re grabbing the right thing.
- Eggs: These will have to be separated and I recommend doing it when they’re cold or the yolks tend to break. The egg whites are used for the meringue and yolks for the key lime filling.
- Honey Graham Crackers: Break them down into crumbs with a food processor or place them in a sealable plastic bag and roll with a rolling pin until broken down. It should resemble a coarse sandy texture.
- Melted Unsalted Butter
- Granulated Sugar
- Cream of Tartar: This helps to stabilize the Italian meringue. You can find it in the spice aisle.
- Vanilla Extract
- Water
How to Make Key Lime Meringue Pie
1. Graham Cracker Crust. First you will combine the graham cracker crumbs, unsalted butter, and granulated sugar. Press it into the pie plate and bake for 10 minutes.
2. Key Lime Filling. As the graham cracker crust bakes, whisk together the sweetened condensed milk, egg yolks, and lastly the freshly squeezed key lime juice. Pour the key lime filling into the baked crust and bake for an additional 18 to 20 minutes. Cool completely before refrigerating overnight.
3. Whip up the Italian meringue. Add granulated sugar and water to a saucepan and heat until it reaches 240 degrees Fahrenheit. Pour the sugar syrup into a stand mixer with the egg whites beating. Add the key lime juice, vanilla extract, and cream of tartar. Continue whisking until the mixture becomes glossy, smooth, and stiff peaks form.
4. The finishing touches. Spread Italian meringue over top of the chilled key lime pie and toast as desired. Sprinkle over key lime zest and cut into 12 equal slices. Serve immediately or refrigerate until you are ready to serve your Key Lime Meringue Pie.
Find the complete recipe instructions with measurements below.
A Few Italian Meringue Tips
This Key Lime Meringue Pie is fairly straight forward to make. It has a simple graham cracker crust and a 3 ingredient key lime filling.
The tricky part is the meringue, but don’t worry because it’s actually very stable and a top rated recipe on my blog. You can read my detailed guide on Italian meringue if you’re nervous.
1. Measure out all your ingredients before starting. Setting an “assembly line” ensures you can hit all steps at the correct time they need to be done.
2. Wipe down your tools with a little white vinegar. This gets rid of any oily residue that would prevent your egg whites from whipping up and stabilizing.
3. Watch out for crystallized sugar syrup. If the syrup is crystallized when you pour it into the whipped egg whites it will create a clumpy, grainy meringue. To avoid this, do NOT stir the sugar and water mixture as it heats up in the saucepan. Also, take an objective look at the syrup before pouring it into the egg whites (it should be clear). If not, throw it out and start again.
Storing Your Meringue Pie
Any leftover Key Lime Meringue Pie can be stored at room temperature for 3 days or in the refrigerator for 5 days. I do recommend placing your pie in an airtight container, like this pie carrier, to keep it fresh as long as possible.
You can also freeze this pie (without the Italian meringue) for up to 3 months. When you’re ready to serve, allow it to thaw out at room temperature, whip up the meringue and finish following the instructions.
Frequently Asked Questions (FAQ’s)
More Yummy Pie Recipes To Try
If you love this Key Lime Meringue Pie we are just getting started, because I love pie!
Key Lime Meringue Pie
EQUIPMENT
- 9 inch pie plate - glass
- Saucepot - small
- stand mixer - with whisk attachment
- thermometer - digital
- kitchen torch - butane
- pie carrier - with lifting tray
INGREDIENTS
Graham Cracker Crust
- 1 cup graham cracker crumbs - about 9 crackers
- 2 tablespoons granulated sugar
- 4 tablespoons unsalted butter - melted
Key Lime Filling
- 1 ¾ cup sweetened condensed milk
- 4 egg yolks - (keep egg whites for meringue)
- 6 tablespoons key lime juice - freshly squeezed
Italian Meringue
- 3 egg whites - room temperature (keep egg yolks for key lime filling)
- 1 cup granulated sugar
- ½ cup water
- 1 tablespoon key lime juice - freshly squeezed
- ½ teaspoon vanilla extract
- ¼ teaspoon cream of tartar
- ½ tablespoon key lime zest - for topping pie
INSTRUCTIONS
- Preheat oven to 350 °F, and center oven rack.
Make the Graham Cracker Crust:
- Combine the graham cracker crumbs, granulated sugar, and melted butter until everything is wet and covered in butter. Pour into an ungreased, glass 9 inch pie plate. Pat down the crumbs using your hand or the back of a metal measuring cup until it is distributed and firmly against the sides and bottom of the pie plate.
- Pre-bake the crust for 10 minutes before removing from the oven. Reduce heat to 250 °F.
Make the Key Lime Filling:
- In a bowl, whisk together the sweetened condensed milk and egg yolks until smooth. Slowly add the key lime juice and continue whisking until well-combined. Pour key lime filling into the baked graham cracker crust.
- Bake for 18 to 20 minutes or until there is a slight jiggle in the center of the pie. Allow it to set and cool to room temperature. Cover and refrigerate overnight (or as little as 1 hour) before moving on.
Make the Italian Meringue:
- Prep for success by place room temperature egg whites into stand mixer with whisk attachment. Add granulated sugar and water into a small saucepan and set on stove. Have the vanilla extract, cream of tartar, and key lime juice measured out and set next to the stand mixer. Finally, set digital thermometer to 240 °F.
- Heat granulated sugar and water mixture over medium heat for 5 minutes. Do not stir at all during this time. After 5 minutes the mixture becomes cloudy, gently stir for 1 minute to break up remaining sugar. Stop stirring and allow the mixture to come to a rapid boil.
- Add digital thermometer probe, increase heat to medium-high and wait until the sugar syrup reaches 230 °F. Once it reaches that temperature, turn stand mixer on highest speed and allow the egg whites to whip to soft peaks.
- Once the sugar syrup reaches 240 °F (this should take 4 to 6 minutes), remove from heat and remove the digital thermometer probe. Allow the sugar syrup to come to a very slow bubble before pouring it into the egg whites in a pencil-sized steam. Be careful to avoid the whisk attachment by pouring it down the side of the bowl.NOTE: If the sugar syrup is crystallized, do not add it to the egg whites. Discard and start over and be mindful to not stir the mixture or heat it quicker than specified.
- Once all the sugar syrup has been added, immediately pour in the freshly squeezed key lime juice, vanilla extract, and cream of tartar. Continue whisking on high speed for 3 minutes.
- Immediately remove the Italian meringue from the bowl (or it can melt on the bottom of the bowl) and place on top of the chilled key lime pie in an even layer. Refrigerate the pie for an additional 5 minutes before toasting with a butane kitchen torch. NOTE: How to Toast Meringue with Oven Broiler. Chill meringue topped pie for 30 minutes. Preheat oven broiler to low, once warmed place pie in the oven to broil for 1 to 3 minutes. Watch closely to prevent burning, and rotate if necessary.
- Garnish with key lime zest, cut in 12 equal pieces, and serve. *storing information below*
RECIPE NOTES
- Can I use regular (Persian) limes instead? Yes. But please note, they are slightly more acidic in comparison to key limes.
- Can I use bottled key lime juice? Technically yes, but I do not recommend it. The pie will have a bitter, artificial flavor taste.
- Will this recipe fit in a pre-prepared graham cracker crust? Yes, the volume of key lime filling and Italian meringue will fit without overflowing.
STORING INFORMATION
- At room temperature, covered or in an airtight container, for up to 3 days.
- Refrigerated, covered or in an airtight container, for up to 5 days.
- Frozen (without meringue layer) for up to 3 months. Thaw pie in refrigerator before making and topping with Italian meringue and serving.
MAKE AHEAD INFORMATION
- Prepare and bake both the crust and filling. Store in the refrigerator, covered or in an airtight container, for up to 3 days before making and topping with Italian meringue and serving.
Metric conversions are calculated automatically. I cannot guarantee the accuracy of this information.
