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How about an easy dessert that tastes like key lime pie but is much easier to make? Meet my Key Lime Cupcakes—soft, fluffy (like a light cake), and bursting with lime flavor. I top them with a tangy cream cheese frosting that packs even more lime and features a fun lime-colored swirl.

Key lime cupcakes with green and white frosting


Everyone loves a good cupcake, and I never shy away from a fun themed one. I’ve made Red, White, and Blue Firework Cupcakes (very patriotic) and Halloween Spider Cupcakes (very spooky). These particular cupcakes have a more refined, elegant theme that’s perfect for summer, and they’ve been one of my most popular recipes since 2017.

Red white and blue stringed frosting to emulate fireworks
A closeup showing the spiderweb cupcake liner, creamy frosting and large spider decoration

Featured Comment:

“These were perfection. I brought them to a work event and I was asked if I would take orders for these in the future. Highly recommend” – K Costello

Table of contents

Ingredients

For the cupcakes:

  • Flour
  • Baking powder
  • Salt
  • Unsalted butter
  • Sugar
  • Eggs
  • Milk
  • Vanilla extract
  • Key lime juice
  • Key lime zest

For the frosting:

  • Cream cheese
  • Butter
  • Powdered sugar (confectioners/icing sugar)
  • Key lime juice
  • Key lime zest
  • Green food coloring
A closeup of the green and white frosting with lime zest

What are key limes?


Key limes are a smaller, rounder, and slightly more yellow variety of lime (almost like mini lemons), known for their tart, aromatic juice and distinctive flavor that’s more intense than regular (Persian) limes. They’re famously used in Key lime pie, a classic dessert from the Florida Keys—hence the name “Key lime.”

A few key facts:

  • They’re about the size of a ping-pong ball.
  • They have thin, slightly yellow-green skin.
  • They’re more acidic and aromatic than regular limes.
  • They contain more seeds and can be a bit harder to juice.

When is key lime season?


Key lime season usually runs from June to September. But just like key lime pie, we all love to enjoy these treats year-round—and you can, because many supermarkets carry bottled key lime juice. If you can’t find it, regular limes work just fine.


For my friends in the UK and around the world, it’s probably regular lime juice for you. Luckily, you can also find it bottled when fresh limes aren’t in season.

1 key lime cupcake on a cake stand

Juicing key limes


Since key limes are smaller than regular limes, they take longer to juice and you need more of them to get the same amount of juice—but the results are worth it because nothing beats freshly squeezed juice. I keep a bottle of key lime juice on hand because there’s nothing more frustrating than dry limes (and yes, it happens).

Lime zesting tip


The zest is the key to that bold lime flavor. Be sure to zest the limes before you juice them—it’s nearly impossible to get zest from a deflated lime, especially a tiny one!


Your eyes aren’t deceiving you—there’s a slight green tint to the frosting. I wanted to give it a hint of lime green, so I added a bit of natural green and yellow food coloring to a small amount of frosting to create a vibrant lime shade. I then spread that colored frosting along the inside of the piping bag before filling it with white frosting. As you pipe, the two mix slightly to create this fun two-tone effect.

A selection of green and white key lime cupcakes

Cupcake baking tips

Bring Ingredients to Room Temperature
Butter, eggs, and dairy mix better when they’re not cold, resulting in a smoother batter and better texture.

  1. Don’t Overmix the Batter
    Once you add the flour, mix just until combined. Overmixing can be easily done when using an electric mixer and can make cupcakes dense or tough instead of fluffy.
  2. Use your mixer on low to medium speed. When you add the flour and powdered sugar, it can get messy.
  3. If using paper liners, buy ones  that are labeled ‘greaseproof’. This will ensure they don’t stick to the cupcakes.
  4. Use a Scoop for Even Sizes. An ice cream scoop helps portion your batter evenly so all your cupcakes bake at the same rate.
  5. Fill Cupcake Liners ⅔ full. Too much batter can cause overflowing or domed tops. ⅔ full is the sweet spot for nicely shaped cupcakes.
  6. Preheat Your Oven Fully. Baking in a properly preheated oven (usually 350°F/175°C) ensures your cupcakes rise evenly from the start.
  7. Don’t Open the Oven Door Too Early. Wait until the cupcakes are nearly done before peeking, or they might sink.
  8. Use the Toothpick Test. Insert a toothpick into the center—if it comes out clean or with just a few crumbs, they’re done.
  9. Cool Completely Before Frosting. Even a slightly warm cupcake can melt frosting and make a mess. A wire rack is best.

Storing cupcakes

Keep cupcakes in an airtight container at room temperature for up to 2 days, or refrigerate if they have perishable frosting (like cream cheese).


If you’ve made my Key Lime Cupcakes please leave a star rating in the recipe card. You can also leave a comment or ask a question below.

Yield: 12 cupcakes

Key Lime Cupcakes

Key lime cupcakes on a cake stand in green and white striped cups

Key lime cupcakes have all the flavors of key lime pie in a pretty little cupcake. Bright and fresh lime flavor that’s a little tart, a little sweet, that make  for a bright summery dessert.

Prep Time 30 minutes
Cook Time 20 minutes
Total Time 50 minutes

Ingredients

  • For the cupcakes:
  • 1 ½ cups (188 grams) all-purpose/plain flour, sifted
  • 1 ½ teaspoons baking powder
  • ½ teaspoon salt
  • 8 tablespoons/½ cup (113 grams) unsalted butter, softened at room temperature
  • ¾ cup (150 grams) granulated sugar
  • 2 large eggs, room temperature
  • ½ cup (118ml) whole milk, room temperature
  • 1 teaspoon vanilla extract
  • 4 tablespoons key lime zest (about 8 small limes)
  • ⅓ cup (78 ml) tablespoons key lime juice
  • For the frosting:
  • 8 ounces (226 grams) cream cheese, softened at room temperature
  • 8 tablespoons (113 grams) unsalted butter, softened at room temperature
  • 2 cups (240 grams) powdered/confectioners/icing sugar
  • 2 tablespoons key lime zest
  • 1 tablespoon key lime juice
  • Green and yellow food coloring (optional)

Instructions

For the cupcakes:

  1. Preheat oven to 350°F (178°C) and place a rack in the center of the oven.
  2. Line a 12-muffin tin with greaseproof liners (these are best so the cupcakes don’t stick).To a bowl, add the flour, baking powder and salt, mix well.
  3. To a large mixing  bowl add the butter and sugar and beat until light and pale using an electric mixer until the butter is lighter in color and fluffy (about 2-3 minutes), scrape the sides down as needed.  Add the eggs, one at a time and beat until mixed. Add the ½  the milk and vanilla, mix well. Add the key lime juice and zest, beat until well mixed. Scrape the sides of the bowl to incorporate into the batter.
  4. Add ½ of the flour mix and mix on slow speed until just mixed (scraping the sides of the bowl). Add the rest of the milk and mix. Add the rest of the flour and mix just until the flour is incorporated.  Switch to using a spatula and gently fold until all the flour is all mixed, do not over mix.Use an ice cream scoop to add divide the batter between all the cups,  just over ½ full.
  5. Bake for 20-25 minutes until the top does not look wet (the time will depend on how your oven is calibrated). Gently press the top of a cupcake — if it springs back, they’re done. When a toothpick inserted in the center it should come out clean.
  6. Remove from the oven and allow to cool in the pan until you can handle them (they will be soft), then remove and cool fully on a wire rack.

For the frosting:

  1. Beat the cream cheese and butter with an electric mixer. Slowly add powdered sugar while beating. Add lime juice zest. Don’t over mix or it will be too soft to pipe.
  2. To get the two-tone piping, transfer 2 tablespoons of the frosting to a separate bowl and mix with the green and yellow coloring until it is lime green.
  3. Refrigerate the frosting for 30 minutes to make it firm for piping
  4. Add the piping tip of choice to a piping bag (I used a 1M star tip). Hold the tip and turn the bag inside out over your hand, add the green frosting to one side of the bag, close to the tip. Use a separate spoon to add the white frosting to the other side of the bag. Whatever ratio you use, you want more white than green. Pipe onto the cupcakes.
  5. More cupcake baking tips.

Notes

Nutrition Information

Yield

12

Serving Size

1
Amount Per Serving Calories 401Total Fat 23gSaturated Fat 14gTrans Fat 0gUnsaturated Fat 8gCholesterol 92mgSodium 248mgCarbohydrates 46gFiber 1gSugar 32gProtein 4g

This nutrition calculation is provided by Nutronix that is only a guideline and not intended for any particular diet.

© Janette
Cuisine: American / Category: Dessert