Key Lime Cupcakes

Soft, zesty, and just the right amount of sweet — these key lime cupcakes are like a slice of summer in cupcake form. If you love the bold citrus flavor of key lime pie but want something easier (and cuter!) to share, these cupcakes are your answer. Light, fluffy cake with a tangy cream cheese frosting that’s got a little lime swirl? Yes, please.

Why I Love These Cupcakes So Much

I’ve made a lot of cupcakes over the years — spooky ones for Halloween, patriotic ones for summer parties, but these? These are in a league of their own. They’re not too flashy, not overly sweet, and have this fresh lime punch that just works, especially on hot days. My family goes nuts over anything citrusy, so when I brought a tray of these to a casual Sunday lunch, they disappeared faster than I expected.

They’ve got that nostalgic key lime pie vibe but are way easier to make and share — and you don’t even need a pie crust.

What You’ll Need for These Key Lime Cupcakes

Here’s the ingredient list broken down simply. You’ll likely have most of this in your pantry already.

For the cupcakes:

• All-purpose flour

• Baking powder

• Salt

• Unsalted butter

• Granulated sugar

• Eggs

• Whole milk

• Vanilla extract

• Fresh key lime juice (or bottled)

• Key lime zest

For the frosting:

• Cream cheese

• Unsalted butter

• Powdered sugar

• Key lime juice

• Key lime zest

• A few drops of green (and optionally yellow) food coloring for that pretty swirl

What’s Special About Key Limes?

Key limes aren’t your average green limes. They’re smaller, rounder, and just a bit yellow when ripe. I’d say they’re the lime version of lemons — extra fragrant, more tart, and way juicier in flavor (not always in actual juice, though!).

They’re the traditional choice for that famous pie from Florida, but I love sneaking them into baked goods. They’re perfect in these cupcakes because they add a little zing without overpowering the cake.

Here’s how to spot them:

• About the size of a ping-pong ball

• Thin, smooth skin

• Pale green to yellowish

• Packed with seeds — so grab a strainer

Can’t Find Fresh Key Limes? Here’s What I Do

If I’m lucky, I’ll spot key limes at my local market around June to September. But most of the time, I just go for bottled key lime juice. It’s honestly a great backup and still gives these cupcakes their signature flavor.

Regular limes will work too if that’s what you have — just add a bit more zest to get close to the same punch.

Quick Tip for Juicing Tiny Limes

Key limes are tiny, and it takes a good handful just to get a few tablespoons of juice. I always microwave them for 10–15 seconds and roll them on the counter with my palm before cutting — makes juicing much easier.

Also, invest in a handheld citrus press. It saves time and strain when dealing with smaller fruits like these.

Don’t Skip the Zest — Here’s Why

The zest is where all the lime magic hides. It’s intensely flavorful and gives the cupcakes and frosting that fresh citrus smell and taste.

Important: Always zest the limes before juicing. Once they’re squished, they’re nearly impossible to zest — especially these tiny ones.

How I Get That Lime Green Frosting Swirl

I wanted the frosting to reflect the lime flavor visually too. I colored a small amount of frosting with natural green and yellow food coloring, then streaked it inside my piping bag before adding the plain white frosting. When you pipe, the swirl happens naturally — no fancy tricks.

This step is totally optional, but it adds a fun, summery pop of color that always makes people smile.

Baking Tips That Always Help Me

I’ve learned these the hard way, so sharing them might save you a cupcake (or a batch):

Use Room Temperature Ingredients

Cold butter doesn’t mix well, and cold eggs can make the batter curdle. Just leave everything out for 30–60 minutes before starting.

Don’t Overmix After Adding Flour

As soon as the dry ingredients go in, switch to low speed or even mix by hand. Overmixing can give you dense, rubbery cupcakes instead of soft and fluffy ones.

Use a Cookie Scoop

Scoop the same amount of batter into each liner — your cupcakes will bake evenly and look more uniform.

Fill Only ⅔ Full

I’ve learned this the messy way. Too much batter means overflow and weird muffin tops. Stick to about ⅔ full — they’ll rise beautifully.

Fully Preheat Your Oven

Give your oven 10–15 minutes extra after the beep to truly settle at 350°F. An oven thermometer helps more than you’d think.

Resist Opening the Oven Door

It’s tempting to peek, but early in the bake, it can make your cupcakes collapse. Wait until they’re golden and almost done before testing.

Toothpick Test

Stick one in the center — if it comes out clean or with just a crumb or two, they’re ready.

Let Them Cool Fully Before Frosting

Don’t rush this. Even slightly warm cupcakes will melt your frosting and make a runny mess. A wire rack works best.

Yield: 12

Key Lime Cupcakes

Print

These Key Lime Cupcakes are like sunshine in a wrapper—soft, citrusy, and topped with a silky swirl of lime-kissed cream cheese frosting.

Prep Time 30 minutes

Cook Time 20 minutes

Total Time 50 minutes

Ingredients

For the cupcakes:

• ½ cup (113g) unsalted butter, softened
• ¾ cup (150g) granulated sugar
• 2 large eggs, at room temperature
• 4 tablespoons key lime zest (about 8 small limes)
• ⅓ cup (78ml) key lime juice
• ½ cup (118ml) whole milk, room temperature
• 1 teaspoon vanilla extract
• 1 ½ cups (188g) all-purpose flour, sifted
• 1 ½ teaspoons baking powder
• ½ teaspoon salt

For the frosting:

• 8 oz (226g) cream cheese, softened
• ½ cup (113g) unsalted butter, softened
• 2 cups (240g) powdered sugar
• 2 tablespoons key lime zest
• 1 tablespoon key lime juice
• Green and yellow food coloring (optional, for a two-tone effect)

Instructions

1. Start by preheating your oven to 350°F (180°C) and lining a standard muffin tin with paper liners.
2. In a small bowl, combine flour, baking powder, and salt—give it a quick whisk and set aside.
3. In a large mixing bowl, beat the softened butter and sugar with an electric mixer until light and fluffy, scraping down the sides as needed. Add the eggs one by one, beating until incorporated.
4. Now stir in the lime zest, lime juice, vanilla, and half of the milk. Mix until everything looks smooth and citrusy. Gently add half of the dry ingredients, then mix in the remaining milk. Finish by folding in the rest of the flour just until no dry streaks remain—don’t overmix!
5. Divide the batter evenly into the cupcake liners, filling each a little over halfway full. Bake for about 20–25 minutes, or until the tops spring back when gently pressed and a toothpick inserted comes out clean.
6. Let the cupcakes cool in the pan for a few minutes before transferring them to a wire rack to cool completely.
7. Make the Frosting : In a bowl, beat the cream cheese and butter until smooth and fluffy. Slowly mix in the powdered sugar, followed by lime zest and juice. Don’t overbeat—it should be smooth but stiff enough to pipe.
8. If you want to add a pop of color, scoop a couple of tablespoons of frosting into a small bowl and mix with green and yellow food coloring to make a vibrant lime green.
9. Chill all the frosting in the fridge for about 30 minutes to firm it up.
10. Fit a piping bag with a star tip (1M works great). Spoon the colored frosting onto one side of the bag, then fill the rest with the white frosting. The swirl will come out with a pretty two-tone effect!
11. Once the cupcakes are completely cool, pipe the frosting on top and enjoy!

Nutrition Information

Yield

12

Serving Size

1
Amount Per Serving Calories 165Total Fat 8gSaturated Fat 5gTrans Fat 0gUnsaturated Fat 3gCholesterol 53mgSodium 296mgCarbohydrates 15gFiber 1gSugar 2gProtein 7g

TastyFitnessRecipes.com, occasionally offers nutritional information for recipes contained on this site. This information is provided as a courtesy and is an estimate only. This information comes from online calculators. Although tastyfitnessrecipes.com attempts to provide accurate nutritional information, these figures are only estimates.

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How I Store These Cupcakes

Because of the cream cheese frosting, I pop them in an airtight container and refrigerate them. They stay fresh for up to 4 days — if they last that long!

If you’re planning to serve them later, I like frosting them just before serving so they look freshly piped and perfect.

A Quick Note Before You Bake

This recipe isn’t fussy, but it does reward patience. Take your time with the zesting, don’t rush the cooling, and use fresh lime juice if you can — those little touches really shine through.

Whether you’re making these for a summer birthday, a brunch table centerpiece, or just a lime-lover’s treat, these key lime cupcakes always bring a little sunshine to the table.

Try other Cupcake recipes:

• Healthy Vanilla Cupcakes
• Vegan Gluten Free Vanilla Cupcakes
• Gluten Free Vanilla Cupcakes