Mom's Best Recipes
Recipe

Key Lime Cake

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

Author 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
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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

Recommended

7Up Pound Cake

7Up Pound Cake

A classic 7Up pound cake with crisp edges, a fine tight crumb, and a lemon-lime glaze that soaks in just enough. Simple ingredients, clear steps, big payoff.

Lemon Bundt Cake

Lemon Bundt Cake

A classic lemon Bundt cake with real zest, a soft crumb, and an easy lemon glaze that soaks in just enough. Reliable, shareable, and not fussy.

Sour Cream Pound Cake

Sour Cream Pound Cake

A classic sour cream pound cake that bakes up plush and rich with crisp edges. Easy ingredients, reliable method, and storage tips so it stays perfect for days.

Orange Cake With Cake Mix

Orange Cake With Cake Mix

A bakery-style orange cake made from boxed cake mix, boosted with real orange zest and finished with a punchy orange glaze. Weeknight-easy, party-ready.

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

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.

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.