Recipe

Key Lime Cake

A tender, zesty lime cake with tangy cream cheese frosting and a bright citrus finish.

By Matt Campbell

•

4.8

A frosted key lime layer cake on a white cake stand, topped with lime zest and thin lime slices on a bright kitchen counter

If you like desserts that make your cheeks do that little happy citrus squint, this key lime cake is for you. It is soft and buttery like classic birthday cake, but with enough lime zest and juice to taste like summer showed up early and brought snacks.

We are going for big key lime pie energy, just in cake form. That means a tender crumb, a lightly tangy lime soak to keep things plush, and a cream cheese frosting that is not shy about it. The whole thing is bright, cozy, and basically impossible not to nibble while you are “just evening the layers.”

A bowl of key limes with a microplane zester and a small pile of fresh lime zest on a wooden cutting board

Why It Works

Real lime flavor from zest plus juice, not just extract.
Tender, moist layers thanks to buttermilk and a quick lime soak.
Balanced sweetness with tangy cream cheese frosting that keeps the whole cake from going flat.
Approachable method with straightforward mixing and easy-to-find ingredients.

Pairs Well With

Storage Tips

How to Store Key Lime Cake

Refrigerator: Because of the cream cheese frosting, store the cake covered in the fridge for up to 4 days. A cake dome is ideal, but plastic wrap works.
Serve it right: For the best texture, let slices sit at room temperature for 20 to 30 minutes before eating. Cold cake is totally fine, but letting it relax a bit makes the crumb softer and the frosting creamier.
Freezer: Freeze unfrosted layers tightly wrapped for up to 2 months. Thaw overnight in the fridge, then frost. You can also freeze frosted slices on a sheet pan until firm, then wrap and freeze for up to 1 month.

A single slice of key lime cake with cream cheese frosting on a small plate with a fork beside it on a linen napkin

Common Questions

Can I use regular limes instead of key limes?

Yes. Key limes are a little more floral and tart, but regular Persian limes make a fantastic cake. Keep the zest amount the same. For the soak, taste the juice first. If it is very sharp, add an extra teaspoon of sugar.

Is bottled key lime juice okay?

It works in a pinch, especially for the cake batter, but fresh zest is non-negotiable. If you use bottled juice, still zest fresh limes so the flavor reads bright instead of one-note.

How do I keep the cake from turning out dense?

Three things: do not overmix after adding flour, make sure your butter and eggs are at room temperature, and measure flour by spooning it into the cup and leveling (or use a scale if you have one).

Can I make this as a sheet cake or cupcakes?

Absolutely. For a 9x13 sheet cake, bake about 32 to 38 minutes. For cupcakes, bake about 18 to 22 minutes. Pan type and oven quirks can shift bake time, so start checking early and use the doneness cues in the instructions.

What if my frosting is too soft?

Chill it for 15 minutes, then beat again briefly. Also make sure you used block cream cheese, not spreadable tub cream cheese. And go easy with extra lime juice because a little goes a long way and too much can loosen the frosting fast.

Matt Campbell

I have always had a huge passion for the culinary arts, people, working as a team, and so on. I wanted to pursue my love for cooking initially at Virginia Commonwealth University with a culinary arts degree; however, I instead decided to apply myself and acquire more practical skills. My end goal is to eventually open my own restaurant or similar establishment.

Kitchen Essentials

2 (8-inch) round cake pans
Parchment paper rounds (recommended)
Mixing bowls
Stand mixer or handheld mixer
Microplane or fine zester
Citrus juicer
Measuring cups and spoons
Wire cooling rack
Offset spatula or butter knife for frosting

I have a weakness for anything lime. It is the flavor equivalent of opening the windows on the first warm day. The first time I tested this cake, I went in thinking, “Cute, citrus cake, whatever.” Then I brushed on the lime soak, tasted a crumb, and immediately started scheming excuses to “trim” the edges again. This is the kind of cake that feels fancy enough for a party, but relaxed enough to slice straight from the pan with a fork while you pretend you are just cleaning up.

Key Lime Cake

(4.8 Reviews)

Prep Time 25 minutes

Cook Time 28 minutes

Total Time 2 hours 30 minutes

Servings 12

Ingredients

For the Cake

2 1/2 cups (300 g) all-purpose flour
2 tsp baking powder
1/2 tsp baking soda
1/2 tsp fine salt
1 cup (226 g) unsalted butter, softened
1 3/4 cups (350 g) granulated sugar
4 large eggs, room temperature
2 tbsp key lime zest (from about 7 to 9 key limes, or 3 to 4 regular limes, depending on size)
1/4 cup (60 ml) key lime juice, fresh (or bottled key lime juice)
1 tsp vanilla extract
1 cup (240 ml) buttermilk, room temperature

Flour, sugar, eggs, butter, buttermilk, and fresh limes arranged on a bright kitchen counter with measuring spoons

For the Lime Soak (Optional, Recommended)

1/4 cup (60 ml) key lime juice
2 tbsp granulated sugar (or superfine sugar)

For the Cream Cheese Frosting

8 oz (226 g) block cream cheese, softened
1/2 cup (113 g) unsalted butter, softened
3 1/2 cups (420 g) powdered sugar, sifted if lumpy
1 tbsp key lime zest
1 1/2 tbsp key lime juice (add more by the teaspoon only if it feels too thick)
Pinch of salt

Garnish (Optional)

Extra lime zest
Thin lime slices or wedges

Instructions

Bake the Cake

Prep the oven and pans. Heat oven to 350°F. Grease two 8-inch round cake pans, line bottoms with parchment, then grease the parchment. Lightly flour the pans and tap out excess.
Mix dry ingredients. In a bowl, whisk flour, baking powder, baking soda, and salt.
Cream butter and sugar. In a stand mixer (or with a handheld mixer), beat butter and sugar on medium-high until light and fluffy, about 3 minutes. Scrape the bowl.
Add eggs and flavor. Beat in eggs one at a time, scraping after each. Mix in lime zest, lime juice, and vanilla.
Alternate dry and buttermilk. Add the dry ingredients in 3 additions, alternating with buttermilk in 2 additions. Mix on low just until combined. Do not overmix. The batter should look smooth and a little airy.
Bake. Divide batter evenly between pans and smooth the tops. Bake 26 to 30 minutes, until a toothpick comes out clean or with a few moist crumbs. If you want a temperature check, aim for about 200 to 205°F in the center. If your oven bakes unevenly, rotate the pans once halfway through.
Cool. Let cakes cool in pans for 10 minutes, then turn out onto a rack and cool completely before frosting.

Make the Lime Soak

Stir lime juice and sugar until the sugar dissolves as much as possible. If it is being stubborn, warm it for 10 to 15 seconds in the microwave (or use superfine sugar), then stir again until mostly dissolved.
When the cakes are fully cool, brush the soak lightly over the tops of each layer, about 1 to 2 tablespoons per layer. Do not drench them. Think: glossy, not soggy.

Make the Frosting

Beat cream cheese and butter. Beat until smooth and creamy, about 1 to 2 minutes.
Add powdered sugar. Add powdered sugar in batches on low so you do not create a sugar cloud. Then beat on medium until fluffy.
Finish with lime. Beat in lime zest, lime juice, and a pinch of salt. Add more juice by the teaspoon only if the frosting feels too thick. Too much juice can soften it quickly. If it feels too soft to frost, chill for 10 to 15 minutes.

Assemble

Level if needed. If your cakes domed, trim the tops with a serrated knife so the layers stack neatly.
Frost. Place one layer on a plate or cake stand. Add a generous layer of frosting. Top with the second layer. Frost the top and sides. This frosting is enough for a thick layer in the middle and a classic finished coat on the outside (not a super-tall, extra-swirly bakery build).
Garnish and chill briefly. Finish with extra zest and lime slices if you want. Refrigerate 20 minutes to help the frosting set, then slice and serve.

A plated slice of key lime cake with creamy frosting and fresh lime zest on top, set on a simple table setting

Nutrition information is estimated.

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Key Lime Cake

Why It Works

Pairs Well With

Recommended

Key Lime Cheesecake

Lechon Belly (Oven-Roasted)

Wilton Buttercream Icing

Vanilla Buttercream

Storage Tips

How to Store Key Lime Cake

Common Questions

Common Questions

Can I use regular limes instead of key limes?

Is bottled key lime juice okay?

How do I keep the cake from turning out dense?

Can I make this as a sheet cake or cupcakes?

What if my frosting is too soft?

Key Lime Cake

Ingredients

For the Cake

For the Lime Soak (Optional, Recommended)

For the Cream Cheese Frosting

Garnish (Optional)

Instructions

Bake the Cake

Make the Lime Soak

Make the Frosting

Assemble