Key Lime Cake
Mouthwatering Key Lime Cake! Easy recipe with just the right amount of tanginess. Moist cake with key lime cream cheese frosting.
It’s been a while since I’ve made a cake!
Today I’m so happy to be sharing a perfect cake recipe for summer: Key lime cake!
This newest addition stands beautifully along with all the other cake recipes on this site: including (but not limited to!) my strawberry cake, chocolate cake, and vanilla cake.
Don’t you think there’s something so special about a layer cake! Doesn’t it just scream “celebration!”?
And like all the others, this one bakes up so moist and soft, and the recipe is easy as can be!
I really enjoyed making it and it came together in no time flat!
I think you’re really going to love the tangy, citrusy flavor of this key lime cake recipe. It’s so refreshing!
Table of Contents
- What is Key lime?
- What does it taste like?
- Key Lime Cake Ingredients
- How to make it
- How to serve it
- Expert tips
- Frequently asked questions
- How to store
- A few more of my favorite citrus recipes
What is Key lime?
Key limes are a special variety of lime that are native to the Florida keys.
They are smaller than the usual type of lime (which are called Persian limes) and they usually have more of a yellow color and a thinner skin.
The flavor is more tart and they are also way more aromatic. The smell is just intoxicating!
Mostly, key limes are used for making key lime pie. But their juice is great for all sorts of different desserts!
Including this gorgeous Key lime cake.
What’s great about this Key lime cake recipe
Here’s what I love about this recipe:
- Perfectly balanced flavors: This cake bakes up just tangy enough, without being overly tart OR too cloyingly sweet. And the Key lime cream cheese frosting is the perfect complement.
- Great texture: The cake layers are moist without being too wet or claggy. And the crumb is fine and uniformly close, so it just melts in your mouth.
- Quick & easy recipe: The recipe is made mostly with basic pantry staples, comes together in a snap, and it’s so easy you don’t even need a mixer.
- Versatile: You can make this cake as a 6-inch round, triple layer cake (as you see here), an 8 or 9-inch round, double layer cake, a 9×13-inch sheet cake, as 24 cupcakes, or you can double it and bake it in a 12-cup bundt pan.
What does it taste like?
The flavor here is really all about the Key lime.
I formulated the recipe as an oil-based cake so that the tangy citrus really comes through.
Usually, I go for a butter-based cake because I just love the richness of butter! But here, I didn’t want anything to stand in the way of the Key lime.
You can use any type of frosting you like, but I’d recommend the Key lime cream cheese frosting included in the recipe card below.
It’s made with just 4 ingredients, the cream cheese complements the cake flavor beautifully, and it’s really easy to work with.
My unique method for making cream cheese frosting results in icing that’s fluffy and stiff enough to create piped decorations. It’s never runny and it crusts over as it sits, making it really easy to plate your sliced cake. You can read lots more about it here: The Best Way to Make Cream Cheese Frosting.
When you taste this cake, you’ll immediately notice the bright, zippy flavor of aromatic Key lime. It’s super-citrusy without being too tart or bitter. Then you’ll get the sweetness of the frosting, which also builds on the sharp Key lime flavor. It’s rounded out with the richness of butter and smooth cream cheese.
Key Lime Cake Ingredients
This easy recipe is made mostly from pantry staples:
Flour
All-purpose flour is my go-to, but you can swap it out for any kind of whole-grain option if you like. You may need slightly less if you go that route. A gluten-free flour blend that can sub 1:1 for regular flour should also work just fine, if you’d like to make a gluten-free Key lime cake.
Sugar
Sugar adds sweetness (obvs!) but it also aids in browning and keeps things moist, since it’s hydrophilic (this means it loves water, in other words, it draws moisture in). Regular white sugar is fine, or sub for another type of sweetener if you like. As long as it swaps 1:1 for granulated sugar it should work.
Baking Soda
Baking soda is used to “leaven” the cake, or make it rise. When baking soda combines with an acid, a chemical reaction happens that creates tons of little bubbles. These bubbles “lift” the cake and make it fluffy rather than dense. Make sure you’re using baking soda and not baking powder. Baking powder has acid added to it to help it activate, and you don’t need that for this recipe!
Salt
Salt carries the flavors and intensifies them. The end result won’t taste salty, but it will make everything so much more flavorful! I like kosher salt best because it doesn’t have any additives (table salt usually contains iodine and that can leave a bitter taste), so the flavor is pure. It’s also inexpensive and easy to find in a regular grocery store.
Lime Zest
Zest is just the outermost, colored part of the skin. It’s loaded with essential oils, which add the most incredible aroma and flavor to foods. To get it, just scratch a microplane grater over the surface of the fruit, making sure not to go too deep into the pith. Pith is the white layer below the zest, and it often has a bitter taste.
Oil
Oil will help to keep the cake moist. I typically use vegetable oil, but any kind of neutral-flavored oil (such as corn oil, peanut oil, canola oil, or avocado oil) will work.
Sour Cream
The high fat content of sour cream adds a richness that will help carry the flavors of the cake. It also adds moisture, and because it’s so thick, it won’t make your batter all drippy. The thick texture produces a tender, fine crumb. If you don’t have sour cream, you can use the same amount of plain, unsweetened Greek yogurt (preferably full fat) or buttermilk.
Butter
Butter is used in the frosting. It provides richness and also helps the buttercream to be nice and stiff.
I like to use unsalted butter because it lets me control the amount of salt in the dish. Different brands of butter can contain different amounts of salt, so this way you get a more consistent result.
For a vegan or dairy free frosting recipe, use a plant-based butter that can substitute for dairy butter 1:1.
This recipe works best if you allow the butter to come to room temperature first. You can set it out on the counter a few hours ahead of making your recipe, or you can microwave it for 10 seconds, turn it over, and microwave it again for another 8 seconds.
Cream Cheese
Cream cheese provides a rich, creamy, slightly tangy flavor in the frosting. Citrus and cream cheese are a match made in heaven!
This recipe works best if you use cold cream cheese, straight from the fridge. Look for the kind that comes in a brick. The kind in a tub could make for a runny frosting. And make sure it’s full-fat! You need the fat for things to whip up properly.
Powdered Sugar
Powdered sugar dissolves easily into the other frosting ingredients, creating a smooth buttercream with just the right amount of sweetness. It also helps the frosting to “crust over.”
How to make it
This cake recipe comes together in just a few simple steps:
Step 1: Combine the dry ingredients
Place the flour, sugar, baking soda, salt, and lime zest in a large bowl.
Give them a quick whisk, just to get them combined.
Step 2: Add the liquid ingredients
Create a well in the center, and add in the oil, sour cream, key lime juice, and egg whites.
Step 3: Combine to make the batter
Working from the center outward, whisk the liquid ingredients together, gradually bringing the dry ingredients into the batter.
When all the dry ingredients have been incorporated, continue whisking until the batter is smooth.
Transfer the batter to your greased and floured cake pan(s).
Step 4: Bake
Place the unbaked cake(s) in a preheated oven.
You’ll know they’re done baking when the tops no longer look wet, when they feel springy to the touch, and when a skewer inserted in the center comes out clean.
Step 5: Cool
Be sure to cool the cake layers completely before filling and frosting them. If you don’t, the frosting will melt!
Step 6: Make the frosting
Beat the butter, cream cheese, and key lime juice together until smooth.
Then stir in about half the powdered sugar. Scrape the bottom and sides of the bowl, then add the rest of the powdered sugar and the salt.
Once combined, whip the frosting on high speed until it’s fluffy and stiff. (But be careful not to over-whip, or it could go runny! As soon as it starts to look stiff, turn off the mixer!)
Step 7: Fill, frost, and decorate the cake
I piped a few swirls and stars on top of my cake, using a jumbo open star tip and a pastry bag.
And I garnished it with a little sprinkling of lime zest for added color!
How to serve it
Slice this cake into individual portions and serve it chilled or at room temperature.
It’s perfect just as-is, but you could garnish it with a slice of lime or add a scoop of ice cream.
Expert tips
Here are a few of my top tips for making Keylime cake:
Keep the door closed
You’ll want to keep the oven door closed as much as possible during the baking process. If you open it too soon, all the hot air will whoosh out and your cake could collapse because the structure isn’t strong enough yet. Turn on the oven light so you can follow visual cues as to when to check the cake. It should no longer look wet or overly shiny.
Don’t under-bake
Every oven is different, so the bake times given are only a rough guideline. If your cake is underbaked, it could collapse. Make sure it’s (at least) close to being done before you start checking it. If it no longer looks wet or shiny, crack the oven door open just the tiniest bit and feel. It should spring back when gently pressed. If it feels at all gooey, shut the door right away and give it a few more minutes. If it bounces right back up, test: insert a skewer into the center. It should come out clean. If the skewer comes out with batter or a lot of crumbs on it, give your cake a few more minutes in the oven.
Don’t over-bake
If you overbake your cake, it could come out dry. Start checking it about 5 minutes before you expect it to be done. If it doesn’t look shiny or wet, follow the instructions above.
Chill the cake layers
I find it so much easier to fill and frost a cake if the cake layers are cold. Wrap them up tightly with plastic wrap and allow them to chill in the fridge, and they’ll feel so much sturdier as you’re working with them!
Use the right kind of cream cheese
Full fat cream cheese in a brick will yield the fluffiest, stiffest frosting. It’s best if it’s cold from the fridge.
Put on a crumb coat
If you notice a lot of crumbs pulling up as you frost your cake, you might want to put on a crumb coat first. A crumb coat is a very thin coat of frosting that catches and seals in all the crumbs. Chill the cake after applying the crumb coat. Once it’s crusted over, add another, thicker layer of frosting. It will be smooth as satin and free of any pesky crumbs!
Frequently asked questions
Can I use regular lime juice?
Regular lime juice will work in a pinch, just as any kind of citrus juice would. But it won’t have quite the same flavor as Key lime juice.
Can I use freshly squeezed juice from real Key limes?
If you can find them, then go for it! I’m sure freshly squeezed Key lime juice is even better than bottled!
Can I make this in a different sized pan?
This recipe works in lots of different ways. You can make it as a
- triple layer 6-inch round cake (like you see in the photos here)
- double layer 8-inch round cake
- double layer 9-inch round cake
- 9×13 sheet cake
- bundt cake (if you double the recipe and use a 12-cup bundt pan)
Or as cupcakes. Just divide the batter equally between all 24 wells of the pan(s).
Keep in mind that if you make this recipe in a different kind of pan, it could affect the bake time. You’ll know your cake is done when it no longer looks shiny and wet, when it springs back when gently pressed, and when a tester inserted in the center comes out clean.
Can I make the batter ahead of time and bake it later?
Honestly, this would be a bad idea.
The baking soda starts to activate as soon as the liquid ingredients go in, so it’s best to bake the cake as soon as the batter is made.
Can I use a different kind of filling?
For the cake you see here, I just used Key lime cream cheese frosting in between the layers.
But you could use any kind of filling you like!
Here are a few suggestions:
- No-Bake Cheesecake
- Ice Cream or Sorbet
- Marmalade (made with Key limes instead of oranges)
- Citrus curd (made with Key lime instead of lemon)
- Chocolate mousse
- Jam
- Vanilla pudding or pastry cream
Can I make the frosting ahead of time?
I prefer to make the frosting right before I plan to use it. That is when it’s at its fluffiest!
But it will keep at room temperature for a day or so. Any longer than that, and it’s best to refrigerate it.
I would not recommend freezing cream cheese frosting. The freeze/thaw process can make it grainy.
You might be able to re-fluff your frosting with the mixer, if it becomes dense or compacted. But watch it very carefully to make sure it doesn’t go soupy.
Can I use a different kind of frosting?
Use any kind of frosting you like on this cake!
You’ll find lots of other options here: Frostings/Icings.
I think the Whipped Cream Frosting would be an especially nice alternative!
How to store
This cake is fine at room temperature for a day or so, unless it’s really hot and then you might have some trouble with the frosting getting too soft.
It should keep in the fridge for around a week, tightly wrapped, or in the freezer for a few months. Thaw it in the fridge or at room temperature.
A few more of my favorite citrus recipes
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Key Lime Cake
Ingredients
For the Key Lime Cake
- 2 1/2 cups (312.5 g) all-purpose flour
- 1 1/2 cups (300 g) granulated sugar
- 1 teaspoon (4 g) baking soda
- 1 teaspoon (6 g) kosher salt, scant
- 1 tablespoon (6 g) lime zest
- 1 cup (224 g) oil
- 1 cup (230 g) sour cream*
- 1/2 cup (121 g) key lime juice
- 2 (60 g) egg whites, from large eggs
For the Key Lime Cream Cheese Frosting
- 1 cup (227 g) unsalted butter, softened
- 8 ounces (226.8 g) cream cheese, cold (the kind in a brick)
- 1 1/2 tablespoons (22.5 g) key lime juice
- 5 cups (600 g) powdered sugar
- 1/8 teaspoon (0.75 g) kosher salt
- 1/2 teaspoon lime zest, optional garnish
Instructions
To Make the Key Lime Cake
- Preheat the oven to 325 degrees F and generously grease three 6-inch cake pans, two 8- or 9-inch cake pans, or one 9×13-inch pan and dust with flour. (Or line the wells of two cupcake pans with paper liners.)**
- Place the flour, sugar, baking soda, salt, and lime zest in a large mixing bowl, and whisk to combine.
- Create a well and add the oil, sour cream, key lime juice, and egg whites.
- Whisk the liquid ingredients together, gradually incorporating the dry ingredients from the outside edge of the well.
- Continue whisking until smooth, then transfer the batter to the prepared pan(s).
- Bake until springy to the touch. A skewer inserted in the center of the cake should come out clean. (Approx. 30 to 40 minutes)
- Cool completely in the pans, then unmold, frost with key lime cream cheese icing, and garnish with lime zest (optional).
To Make the Key Lime Cream Cheese Frosting
- Place the butter, cream cheese, and key lime juice in a large mixing bowl, and beat on medium-low speed until smooth.
- Scrape the bottom and sides of the bowl with a silicone spatula, and add about half the powdered sugar.
- Stir in the powdered sugar until combined, then scrape the bottom and sides of the bowl again, and add the remaining powdered sugar and the salt.
- Stir together until combined, then turn the mixer up to medium-high speed and whip until the frosting is fluffy and stiff. (Be careful not to over-whip the cream cheese frosting, or it could become runny. As soon as the frosting looks stiff, turn off the mixer and use the frosting immediately.)
Great key lime cake. Super moist. The icing is the best key lime I’ve ever tasted. Then I made up another key lime batter and made cupcakes! Sprinkled lime zest over the top. Yum! Took to the Sunday Church potluck and received rave reviews! Since it is a very moist batter, I preferred working with the cupcakes.
Thanks so much for the positive feedback Carol!