Key Lime Cake is light, fluffy, sweet, and tangy. Flavored with coconut extract and lime juice, and topped with rich cream cheese frosting.
If you’re a fan of Key Lime Pie, then you’re sure to love this delicious Cake Recipe. Like the famous citrus and custard pie, it has the perfect combination of sweet and tangy flavors but in a delicious showstopping layer cake.
About our Key Lime Cake Recipe
This easy recipe uses a classic cake batter with simple pantry ingredients as the base. You’ll add key lime and coconut for a refreshing, summer flavor. It’s the perfect dessert to enjoy with your family or bring to a party as the weather gets warmer. Along with the tasty, tender cake, this cake has a delicious layer of key lime Cream Cheese Frosting. The sweet and tangy flavor of thick, cream cheese frosting goes perfectly with the citrus flavor of the lime cake. Serve with rich Vanilla Ice Cream to complete the summery dessert.
Key Lime Cake Ingredients
- Butter: Softened butter is creamed with white sugar to make the fluffy, airy consistency you want for your cake. If you try to use cold butter, it could make your cake dense.
- Milk: Using whole milk in cake recipes helps to create rich cake crumbs. The milk will help to soften the dry ingredients and activate the leavening agents. For best results, bring the milk to room temperature before starting your cake batter.
- Lime Juice: To give this key lime recipe the classic flavor you want, real key lime juice to the cake batter. It will taste best if you buy fresh key limes and juice them yourself. You’ll also add the key lime juice to the cream cheese frosting for extra lime flavor.
- Flour: When baking cakes, an easy way to make sure they turn out light and airy is to use cake flour instead of all-purpose flour. If you sift your regular flour though, it can help get that cake flour texture without using the special blend.
- Cream Cheese: Bring the cream cheese to room temperature so that it’s softened before blending it with the butter and sour cream to make the frosting. Full-fat cream cheese creates a rich, thick base for the frosting, that lightens up into a more fluffy mixture as you combine it with the other ingredients.
- Sour Cream: Adding cream cheese enhances the slightly tart flavor of the frosting. It’s a little lighter than cream cheese, so it doesn’t weigh the frosting down.
- Sugar: You use powdered sugar to sweeten the cream cheese frosting without adding texture so it’s smooth and fluffy.
- Condensed Milk: Brush the cooled cakes with sweetened condensed milk. This adds more wonderful, creamy flavor to the Key Lime Cake, and helps keep the cake moist longer.
Kitchen Tools & Equipment
- Cake Pans: You can use different cake pan shapes and sizes. However, if you alter the size too much, you’ll have too much or not enough batter. You can fairly seamlessly, switch the recipe into a 9? cake pan or swap out a circle cake dish for a square one. Just keep in mind that the layer of batter will be thinner in a 9? pan, so the cakes will bake faster.
- Piping Bag: A standard piping bag and a 1 inch tip are all you need to make a gorgeous cake. The key is to not overfill your bag and to take your time when piping. And of course, start with a completely cooled cake so it doesn’t melt.
How to Make Key Lime Cake
Time needed: 4 hours.
- Prep Work
To start, preheat your oven. Grease two 8 inch cake pans with butter, and add a dusting of flour. Bring your ingredients to room temperature.
- Make the Cake Batter
Sift the flour, baking powder, and kosher salt into a medium bowl and set the dry ingredients to the side. Cream the butter and sugar in your stand mixer. Add one egg at a time, then add the coconut extract and fresh lime juice, and set the mixer speed to low. Alternate between adding a little of the flour mixture and the milk until both are added to the mixing bowl. Add the green food coloring, a few drops at a time, until the cake has a beautiful lime green color.
- Bake the Cake
Pour the cake batter into the prepared cake pans. Then bake for 25-30 minutes or until a toothpick inserted in the center of the cake comes out clean. Let the Key Lime Cakes cool before removing them from the pan and frosting.
- Make the Frosting
Add softened cream cheese frosting, butter, sour cream, lime juice, lime zest, and vanilla extract to your stand mixer and beat until light and fluffy. Then add the powdered sugar one cup at a time until the mixture is smooth. Optional: Add a few drops of green food coloring until the frosting has the desired lime green color.
- Assemble the Cake
Add a spoonful of key lime frosting to your cake stand. Then use a large serrated knife to level the cool cakes and discard the cake pieces and excess crumbs. Add the first cake layer to the cake stand, then brush it with ¼ cup condensed milk. Top the cake with 1 cup of fresh lime frosting and spread it evenly. Then add the second layer of cake, and brush ¼ cup of condensed milk over the top. Add another cup of frosting on top and spread evenly.
- Set the Crumb Coating
Put the cake in the fridge for 30 minutes to allow the first coat of frosting to harden. This time in the fridge will allow you to add a clean top layer of frosting without any cake crumbs in it.
- Decorate the Cake
Use an offset spatula to frost the entire cake with half the remaining frosting. Then add the remaining frosting to a piping bag and pipe swirly mounds onto the top of the cake. Twist lime slices into an “s” shape and add them to the top of the cake. Then grate fresh lime zest over the top as a garnish.
Key Lime Cake Recipe Tips & Tricks
Get light and fluffy cakes that are cooked perfectly with these cake baking tips.
- Don’t Over Mix the Batter
- The key to light and fluffy baked goods is to not overmix the batter once you add the flour and other dry ingredients. Mixing the flour too much will make your cake dense because it makes it more glutenous. Just mix until there are no dry streaks.
- Start with Room Temperature Ingredients
- Unless a recipe calls for cold ingredients, it’s a good practice to have all your ingredients to be room temperature. Not only is it easier to mix things like eggs and butter, but it prevents cold spots in your batter so it bakes evenly.
How to Store Key Lime Cake
- Serve: After frosting the cake, let it set for a few minutes before slicing and serving. You don’t want to leave the cake uncovered at room temperature for more than a few hours, or it will start to dry out.
- Store: To keep the leftover cake fresh, put it under a cake cover, cover it in plastic wrap, or store individual pieces in an airtight container. The cake will stay fresh at room temperature for 3-4 days.
- Freeze: To freeze the cake, carefully wrap it in plastic wrap, followed by a layer of aluminum foil. It can stay good frozen for up to 3 months. Then let the cake thaw at room temperature before serving.
FAQ for Key Lime Cake
Key limes are generally smaller and rounder than regular limes. Key limes also taste different. They still have a citrusy flavor, but they aren’t quite as tart and are instead known for a slightly sweeter, more aromatic flavor.
If you don’t have access to key limes, you can instead use half lime juice and half lemon juice. The combination of citrus flavors mimics the tangy, sweet flavor you’d get from key limes.
Key Lime Layer Cake:
- 3/4 cup unsalted butter
- 1 1/3 cups sugar
- 3 large eggs
- 1/2 teaspoon coconut extract
- 1 cup whole milk , room temperature
- 1/4 cup key lime juice
- 2 1/3 cups flour
- 2 1/4 teaspoons baking powder
- 1/2 teaspoon salt
- 4-6 drops green food coloring , optional
Key Lime Cream Cheese Frosting:
- 24 ounces cream cheese , softened
- 1/2 cup unsalted butter , softened
- 3 tablespoons sour cream
- 3 tablespoons key lime juice
- 1 teaspoon vanilla extract
- 6 1/2 cups powdered sugar , about 2 pounds
- 4-6 drops green food coloring , optional
- 1/2 cup condensed milk , for brushing
Key Lime Layer Cake:
- Preheat the oven to 350 degrees and butter and flour two 8" cake pans.
- Sift together the flour, baking powder and salt then set aside.
- To your stand mixer add the butter and sugar and beat them together until light and fluffy on medium speed, 2-3 minutes, then add in the eggs one at a time 15 seconds apart along with the coconut extract then lower the speed to low.
- Add the flour mixture and milk, alternating a little of each at a time.
- Add in the green food coloring until you get a beautiful lime color, starting with just a drop at a time.
- Pour into the cake pans evenly and baked for 25-30 minutes until a toothpick comes out clean.
- Cool cakes completely before frosting.
Key Lime Cream Cheese Frosting:
- Add the cream cheese, butter, sour cream, lemon juice, lemon zest and vanilla to a stand mixer and beat until light and fluffy.
- Add in the powdered sugar one cup at a time until smooth and incorporated.
- Add in the green food coloring until you get a beautiful lime color, starting with just a drop at a time and stir.
- To your cake stand add a spoonful of frosting.
- Level the cakes with a large serrated knife and discard the cake pieces.
- Brush off excess crumbs.
- Add the first layer of the cake to the cake stand.
- Brush with ¼ cup condensed milk.
- Top with 1 cup of frosting, spread evenly.
- Top with second layer of cake.
- Brush with ¼ cup condensed milk
- Top with 1 cup of frosting on top, spreading evenly.
- Add 1 cup of frosting, coating the outside of the cake.
- Refrigerate for 30 minutes to allow to harden.
- Frost the cake with half the remaining frosting.
- Pipe swirly mounds onto the top of the cake.
- Add thin slices of limes to the cake, cutting through one segment and twisting to create an "s" shape.
- Grate fresh lime zest over the cake as a garnish (if you used key lime juice that is bottled, just zest from a normal lime).
Key Lime Cake Variations
Citrus Cake: If you prefer, you can swap out the lime flavor in this recipe for other citrus flavors, such as freshly squeezed orange juice or fresh lemon juice.
Frosting: If you prefer, you can make this recipe with Buttercream Frosting in place of cream cheese frosting. Add lime flavoring to the classic buttercream mixture, so that it still has key lime flavor.