Perfectly tart with the right amount of sweet, this key lime cake recipe from scratch holds a special place in our hearts (and stomachs!).
The top layer of our wedding cake was key lime cake. We had it recreated for our first year anniversary. Since our 10 year wedding anniversary is a few short days away, I couldn’t resist sharing this recipe on the blog. How else does one celebrate such a milestone without cake? In fact, by the time our anniversary rolls around, I’ll have posted recipes for all three tiers of our wedding cake. Can you guess which?
If you spend any amount of time reading the blog, you’ll realize that the Godfather and I really really love key limes. There are recipes for key lime cookies, tart, margaritas, cheesecake, macarons… even tacos! I think our Floridian roots are a little obvious, haha. It only makes sense we had key lime cake at our wedding, doesn’t it?
What I really love about this recipe for key lime cake is the flavor! And I get this great lime flavor without using lime extract! I don’t know about you, but I don’t find lime extract easily where I live. Therefore, all natural lime cake flavoring is the way to go. The best part is, a great lime flavor in the cake opens up the possibilities for all sorts of frostings and fillings.
I opted for a white chocolate butter cream frosting and filling in these photos, which is just a slight variation on your standard American buttercream. White chocolate provides the perfect compliment – in my opinion – to balance the cake. If you’d prefer to use something else, we’ve also liked cream cheese frosting, classic American buttercream, and pretty much any vanilla or vanilla bean icing. If you want a very pronounced lime flavor, lime curd is a great option.
What are key limes and what do I do if I can’t find them?
Key limes, in case you’re unfamiliar, are small limes grown in tropical climates – like the Florida Keys. They are a bit higher in acidity than a “standard” lime and has more of a sweet tart flavor. This is why key limes are so popular in dessert recipes.
You should be able to find key limes in the produce section of your grocery store. It’s often sold in 1-2 pound bags. If you can’t find key limes though, DON’T STRESS! You can absolutely substitute the Persian limes you find at the store. Persian limes are the “normal” lime variety we can find basically anywhere year round. I’ve made this cake with both varieties and it’s always turned out with a great lime cake flavor.
What is “reverse creaming” a cake, and why does it matter here?
Reverse creaming is a cake mixing technique where you add your dry ingredients to your main mixing bowl first and then add the wet ingredients. In this particular recipe, it’s very important to give you a light and tender cake. I go into a full explanation in the video on this page – definitely worth a watch – but basically you need this to get the best lime cake from scratch possible!
With a reverse creaming method, you don’t shock the other ingredients with the acid in the lime juice, so you still keep a tender crumb. You’ll actually see a difference in the crumb of the cake from the photos to the video and a lot of it is due to the method! And the updated cake is definitely a winner… a repeat was requested by friends almost immediately after the first cake was finished!
I’m going to go out on a limb and say this was even better than our wedding cake! This tender lime cake recipe has solidly earned a spot in my family’s “top three cake recipes of all time” list. I hope you all enjoy it as much as we do!
Key Lime Cake
- 2 2/3 cups cake flour
- 2 cups granulated sugar
- 1/2 teaspoon kosher salt
- 2 teaspoons baking powder
- 16 tablespoons unsalted butter, softened
- 4 large eggs
- 1 cup buttermilk, room temperature
- 2 tablespoons vegetable oil
- 1 tablespoon lime zest
- 1/2 cup freshly squeezed lime juice
White Chocolate Buttercream Frosting
- 12 ounces white chocolate, 340 g
- 3 ounces heavy cream, 85 g
- 2 g sticks unsalted butter, 240, softened
- 5-6 cups powdered sugar, 568 - 681 g, sifted
- 1 tsp salt
- 1 tsp vanilla extract
- Preheat your oven to 350 F. Butter and flour 2 8" cake pans or place liners in 2 dozen cupcake wells. Set aside.
- Combine the flour, sugar, salt, baking powder, and key lime zest in a mixing bowl or stand mixer fitted with the paddle attachment. Stir briefly to combine.
- Add the oil and then the eggs, one at a time. Scrape the sides of the bowl as needed. Stir in the buttermilk and finally, the lime juice. Stop stirring as soon as everything is combined.
- Evenly distribute the batter between the pans.
- Bake 30-40 minutes until a tester comes out clean and you see the cakes just start to slightly pull away from the edges of the pan.
- Remove from the oven and allow to set for 10 minutes before turning cakes onto a cooling rack to cool completely before frosting.
To Make the Frosting:
- In a double boiler or in the microwave, melt together the white chocolate and heavy cream until smooth.
- In a clean bowl with a hand mixer, or using the paddle attachment on your stand mixer, beat the butter until light and fluffy. Scrape the sides of the bowl.
- Add two cups of powdered sugar, beating and scraping the bowl after each addition. Then pour in your white chocolate ganache and stir until incorporated.
- Add the remaining three cups of powdered sugar, one at a time, then stir in the salt and vanilla extract.
- Mix the frosting on low speed for 5-6 minutes.
- If your frosting is too thick, add a little heavy cream to thin. If it's too thin, add additional powdered sugar.
- Use immediately, covering with a damp cloth as you work so the buttercream doesn't crust.
The cake layers can be made up to 2 days in advance, wrapped in plastic wrap while slightly warm and refrigerated until you are ready to frost. Chilled cakes are easier to work with!