Excite your taste buds with this flavorful key lime icebox cake made with graham crackers, key limes, and whipping cream. Anyone who loves key lime pie or a citrus kick will love this tasty layered dessert. The best part is how easy it is to make and it requires no bake time! For anyone looking for an easy dessert, it doesn’t get any better than the tangy layers of creamy lime filling in this delicious dessert.
Anyone who knows me knows I how much I enjoy sweet fruity things, like this delicious citrus strawberry mocktail.
This key lime pie icebox cake is right up my alley with the perfect balance of sweet and tangy from the layers of citrusy creamy filling, sweet graham crackers, and homemade whipped topping.
Plus, it’s stored in the fridge which makes it perfect for those hot summer days when you want something light and refreshing.
Fun fact: icebox cakes have been around for over a century. There’s a reason these simple no bake desserts have spanned the test of time. They are delicious, versatile, and can be made ahead of time. They’re the perfect dessert for summer pool parties, family night, or even a Cinco De Mayo party.
Why You’ll Love This Recipe
- Make ahead of time – nothing better than an easy recipe that can be made the day before without compromising on taste, like this ice box cake.
- Feeds a crowd - with lots of layers and packed full of flavor, a little of this cake goes a long way. It’ll surprise you how many it can feed, and if that’s still not enough, it can easily be doubled.
- No ovens required – no need to make your house even hotter by turning the oven on. This tasty cake is set up in the freezer instead, a no bake recipe that’s perfect for those warmer months.
- Half-and-half - substitute heavy cream for a thicker texture or whole milk for a lighter version. You can also make your own by mixing equal parts whole milk and cream.
- Key limes – regular limes work just fine and are easier to juice and zest. Fresh lime zest and freshly squeezed lime juice are best for flavor, though you can substitute if you want.
- Graham crackers - these need to be the full crackers not graham cracker crumbs.
- Heavy whipping cream - substitute Cool Whip instead of making your own whipped cream.
- Egg yolks – it’s important to only get the egg yolk, not the egg white in this recipe.
How to make Key Lime Icebox Cake
Now on to the fun part – cooking, and of course eating the cake.
If you are making curd for the first time it can be tricky, but you’ll find detailed instructions and pictures below to help you get it right on the first try. You’ll find a printable recipe card at the bottom of the post.
1- Make The Key Lime Curd
Start by adding the egg yolks and half and half to a small bowl and whisk together until fully combined.
In a medium saucepan add the sugar and cornstarch together and whisk until evenly combined. Turn the stove to medium heat and slowly add in the egg yolk and half and half mixture.
After the egg yolk mixture and sugar mixture have been added to the saucepan, let them come to a boil while constantly whisking. This will keep the mixture from burning or sticking to the bottom of the pan. Let it bubble for one minute, while stirring, then immediately remove the saucepan from the heat.
While the mixture is still hot, whisk in the butter, key lime zest, and key lime juice. The butter should melt as you whisk it into the sugar mixture. Once full incorporated, let the ingredients cool in the saucepan for about 10 minutes.
2- Create The Cake
While the curd cools in the saucepan, line a square 8×8 baking dish with plastic wrap. You’ll want to make sure all sides are fully covered so the cake doesn’t stick to the pan and so you can easily lift the cake out of the pan.
For the first layer of the cake, line the bottom of the 8×8 pan with a single layer of graham crackers. It’s easiest to line them three across and then break a few apart to fill in the ends. You’ll want the graham crackers as close as possible to make a good base for the rest of the cake.
After the key lime curd has cooled for 10 minutes, spoon roughly 3/4 cup curd over the top of the crackers to create an even layer of key lime curd.
Repeat with three more layers of graham crackers and custard, add the last layer of graham crackers over the fourth layer of custard. Then cover the pan and place in the freezer for at least eight hours or overnight.
When you are ready to serve the cake, remove the cake from the freezer. Then using the plastic wrap, carefully remove cake from the pan. Take the cake out of the plastic wrap and allow it to sit out for an hour to unthaw before topping and serving.
3-Make The Whipped Cream
While the cake thaws for an hour, make the whipped cream topping.
In a medium bowl, add in the whipping cream and powdered sugar. Use a hand mixer on medium high speed and mix until soft peaks form. You can also use a stand mixer fitted with a whisk attachment on high speed to do this.
4 – Serve the Key Lime Ice Box Cake
Spread the whipped topping onto the top layer of crackers and use key lime slices on top of cake for garnish. You can also use key lime zest if you’d like!
Expert Tips And Storage Info
Play around with the flavors by making a lemon and honey curd instead of key lime. Or add a layer of sweetened condensed milk on the graham crackers before the curd for added sweetness.
Invest in a reamer to help make juicing those little key limes easier.
Store in an airtight container in the fridge for up to three days.
Store in the freezer for up to one month. Allow the cake to thaw for at least an hour before eating if you freeze.
The ice box cake can sit out safely for up to four hours, but layers can get soggy or even melt if in high heat. I recommend keeping it chilled until you’re ready to serve and then just bringing it out to serve immediately.
An icebox cake gets its name from when refrigerators were actually called iceboxes, back in the 1920s. Since this cake sets in the freezer rather than baking in an oven, it was called an icebox cake.
While technically you could use regular limes in this key lime icebox cake recipe, I don’t recommend it. Key limes have a different flavor than regular limes, which is why they’re so often used in desserts. I’d wait until you can get your hands on key limes or make it with a lemon curd instead.
More Easy Summer Desserts
If you want some more refreshing summer desserts, try out some of these popular summer favorites!
- Strawberry cake mix brownies – the combination of cake mix plus fresh strawberries makes these the ultimate summer dessert!
- Lemon cupcakes – light and fluffy lemon flavored cupcakes topped with the best cream cheese frosting.
- No bake banana split cake – another great summer dessert full of everything you’d expect in a banana split!
- Strawberry ice cream cake – fresh strawberries, ice cream, and a golden crust make this a delicious refreshing dessert!
- 3-ingredient Oreo cake – another ice cream cake that’s full of chocolate and Oreo flavor!
Easy Key Lime Icebox Cake
Key Lime Icebox Cake
- ¾ cup granulated sugar
- ¼ cup cornstarch
- 4 large egg yolks
- 2 cups half and half
- 3 TBS butter
- 2 TBS key lime zest about 5-6 key limes
- ½ cup key lime juice about 4 key limes
- 15 graham crackers
- 1 cup heavy whipping cream
- ¼ cup powdered sugar
Key Lime Icebox Cake
- In a medium saucepan add the sugar and cornstarch together and whisk until evenly combined.3/4 cup granulated sugar, 1/4 cup cornstarch
- Turn the stove to medium heat and slowly add in the egg yolk and half and half mixture. Bring to a boil, whisking constantly.4 large egg yolks, 2 cups half and half
- Once boiling, let the mixture bubble for one minute, then immediately remove the saucepan from the heat and whisk in the butter, key lime zest, and key lime juice. Keep whisking until the ingredients are completely incorporated into the mixture.3 TBS butter, 2 TBS key lime zest, 1/2 cup key lime juice
- Line an 8×8 square baking dish with plastic wrap, including the sides.
- Line the bottom of the 8×8 pan with a single layer of graham crackers. It’s easiest to line them three across and then break a few apart to fill in the ends.15 graham crackers
- After the key lime curd has cooled for 10 minutes, spoon roughly 3/4 cup curd over the top of the crackers to create an even layer of key lime curd.
- Repeat with three more layers of graham crackers and custard, add the last layer of graham crackers over the fourth layer of custard. Then cover the pan and place in the freezer for at least eight hours or overnight.
- Just before serving, remove the cake from the freezer and using the plastic wrap, carefully remove the cake from the pan. Allow to thaw for an hour. t
- Top with whipped cream. Slice and garnish with key lime zest and key lime wedges if desired for seving.
- Add the whipping cream and powdered sugar to a medium bowl and mix with a hand mixer on medium high speed (or in a stand mixer) until soft peaks form.1 cup heavy whipping cream, 1/4 cup powdered sugar