Key Lime Cake with Key Lime Cream Cheese Frosting

A Taste of Sunshine: My Key Lime Cake With Key Lime Cream Cheese Frosting

If there’s one dessert that can instantly transport me to a breezy front porch in Florida, it’s classic Key lime cake—with a tangy Key lime cream cheese frosting, of course. Every time I bake this cake, I’m reminded of family vacations spent chasing sunsets and sharing sweet, citrusy treats beneath swaying palms. There’s something downright magical about the way the bright, zesty flavor of Key limes bursts through each bite, mingling perfectly with the silky smooth cream cheese frosting. If you’re looking for a Key lime cake recipe that delivers both nostalgia and wow-factor, you’ve found a new favorite.

Why You’ll Adore This Key Lime Cake

Let me tell you, this Key lime cake holds a special place in my heart (and likely will in yours, too):

• It’s like a vacation on a plate. The vibrant, tart Key lime flavor is guaranteed to brighten any day—even when you’re nowhere near the tropics!
• Unbelievably easy. Using a box cake mix as the base means you get show-stopping results with minimal effort (hello, stress-free baking!).
• Ultra-moist and fluffy. Buttermilk and eggs work wonders here, making every forkful tender and irresistible.
• That irresistible Key lime cream cheese frosting. It’s tangy, creamy, and the perfect finishing touch. You’ll want to eat it by the spoonful (trust me, I have).

Ingredients You’ll Need for Key Lime Cake With Key Lime Cream Cheese Frosting

Here’s everything you’ll need to make this Key lime cake. I’m adding a few personal notes, too—so you get all my best tips!

For the Key Lime Cake:

• 1 box white cake mix (15.25 oz): Feel free to use your favorite brand. Trust me, no one will guess it’s from a box!
• 1 cup buttermilk: The secret to a cake that’s extra-moist and slightly tangy. You can sub in 1 cup milk + 1 tbsp lemon juice if needed.
• 1/3 cup vegetable oil: I stick with classic canola or vegetable for neutral flavor.
• 4 large eggs: Bring them to room temp for the fluffiest batter.
• 1 tbsp Key lime zest: Fresh zest makes all the difference here! If you can’t find Key limes, regular limes work in a pinch.
• 1/3 cup Key lime juice (fresh or bottled): Bottled Key lime juice (like Nellie & Joe’s) is great if you’re short on fresh fruit.
• A few drops green food coloring (optional): For that fun, tropical hue.

For the Key Lime Cream Cheese Frosting:

• 8 oz cream cheese, softened: Full-fat yields the richest frosting—go for it!
• 1/2 cup unsalted butter, softened: Letting it sit at room temp ensures a smooth frosting.
• 3 1/2–4 cups powdered sugar: Adjust to your sweetness and consistency preference.
• 2 tbsp Key lime juice & 1 tsp Key lime zest: Adds a fresh punch to every swirl of frosting.
• 1/2 tsp vanilla extract & pinch of salt: These balance out the sweetness and brighten the flavors.

Step-by-Step Guide: Making the Perfect Key Lime Cake

Let’s get baking! I promise, if you can stir a bowl and spread frosting, you’ve got this Key lime cake covered.

1. Preheat your oven to 350°F (175°C). Grease and flour two 8- or 9-inch round cake pans, or line with parchment (for easy release!).
2. Mix the cake batter. In a large bowl, combine cake mix, buttermilk, oil, eggs, Key lime juice, and zest. Beat on medium for 2–3 minutes until smooth. If you want that festive green hue, add a few drops of food coloring here (my kids always insist on this step).
3. Pour and bake. Divide the batter evenly between the prepared pans. Bake for 25–30 minutes, or until a toothpick inserted comes out clean. (Tip: If your kitchen smells like a Key lime grove, you know it’s almost ready!)
4. Cool completely. Don’t rush this step—warm cake + frosting = slippery mess.
5. Make the frosting. In a clean bowl, beat cream cheese and butter until fluffy (about 2 minutes). Gradually add powdered sugar, then mix in Key lime juice, zest, vanilla, and salt. If the frosting feels too soft, a quick 15–20 minutes in the fridge helps.
6. Assemble and decorate. Place one cake layer on your serving plate, slather on a thick layer of Key lime cream cheese frosting, top with the second layer, and cover the top and sides. Garnish with lime slices, zest curls, or a sprinkle of crushed graham crackers.
7. Slice & enjoy! This is my favorite part—sharing it with good friends (or just sneaking a slice with late-night tea).

My Secret Tips and Tricks for Key Lime Cake Success

• Bring all your cold ingredients to room temperature. This helps everything blend beautifully for a smooth, lump-free batter and frosting.
• Don’t skip the zest! It brings such a fresh, authentic Key lime flavor—bottled juice just can’t replace it completely.
• Chill the cake for 20–30 minutes before frosting if you have time. It makes the crumb less likely to mingle with your beautiful cream cheese frosting (no more crumbly mishaps).
• For even layers: Use a kitchen scale to weigh the batter into each pan. Sounds fussy, but it makes a gorgeous, bakery-worthy cake.
• Key lime cream cheese frosting too runny? Just pop it in the fridge for a few and it’ll stiffen right up!
• No Key limes? Persian limes work really well—and they’re much more common in stores.

Creative Variations and Ingredient Swaps

Life (and baking) is about having fun, so try these simple swaps and variations to make this Key lime cake truly your own:

• Cupcakes instead of cake: Bake the batter in lined muffin tins for about 16–18 minutes. Perfect for sharing!
• Make it gluten-free: Substitute a gluten-free white cake mix and check the other ingredients for gluten.
• Dairy-Free Dream: Use non-dairy buttermilk (combine oat milk + lemon juice) and swap in plant-based cream cheese and butter for the frosting.
• Add a graham cracker crust layer: Press crushed graham crackers mixed with melted butter into the bottom of each pan before adding the batter for bonus “Key lime pie” vibes.
• Coconut twist: Fold 1/2 cup shredded coconut into the batter for extra tropical flair.
• Berry beautiful: Sprinkle fresh raspberries or blueberries between layers for a bright pop of color and flavor.

How to Serve and Store Your Key Lime Cake With Key Lime Cream Cheese Frosting

Serving Tips:

• I love garnishing mine with thin slices of lime, a generous grating of zest, or a cloud of whipped cream.
• Fresh berries on the side are a real treat, too.
• For clean slices, run your knife under warm water between cuts.

Storing Leftovers:

• This frosted Key lime cake stores beautifully in the fridge! Just cover it tightly (I use a cake dome or plastic wrap).
• Leftover slices stay moist and flavorful for up to 5 days—if they last that long!
• If you want to make it ahead, you can bake the cake layers, wrap them tightly, and freeze for up to 2 months. Thaw overnight in the fridge, then add your Key lime cream cheese frosting fresh.

FAQs: Your Top Questions About Key Lime Cake Answered

Can I use regular limes for Key lime cake?
Absolutely! While Key limes add a unique floral tang, standard Persian limes will still yield a delicious, zesty cake (and are usually easier to find).

Can I make Key lime cream cheese frosting ahead of time?
You bet. Store it in an airtight container in the fridge for up to 3 days. Let it soften a bit at room temp and give it a quick whip before frosting.

Do I have to use food coloring?
Nope! The green food coloring is just for fun and won’t affect flavor—skip it if you prefer a more natural look.

Why is my frosting too soft?
Warm kitchens and soft butter can make Key lime cream cheese frosting a bit too gooey. Chill it for 15–20 minutes and it’ll thicken right up.

Can I freeze this cake?
Yes! I suggest freezing the cake layers (unfrosted), then thawing and frosting before serving. Frosted cake slices freeze fine, too—just wrap well to keep them fresh.

Seriously, if you crave a cake that’s tangy, sweet, and a true showstopper, this Key lime cake with Key lime cream cheese frosting is pure joy in every bite. I can’t wait for you to try it—here’s to making bright, citrusy memories in your own kitchen. If you bake it, let me know how it turns out (and what memories you create along the way!).