Nothing quite says, “summer” like key lime pie. The citrusy sweet flavors, crisp graham cracker crust, and a dollop (or two) of light whipped cream. Yum!
Similarly, these key lime pie cupcakes encompass all of the best aspects of the quintessential summertime treat in an easy-to-eat, little confection.
The tender vanilla cake sits atop a crunchy, graham cracker crust, is filled with fresh key lime curd, topped with light key lime buttercream, and finished off with a candied lime slice.
I first started testing this recipe last year in Florida. Blame it on the tropical heat, but I was inspired! After a few too many trial cupcakes, the perfect blend of ingredient measurements finally came together.
Since then, I’ve baked these cupcakes many times, always met with rave reviews. In fact, these have become my second most-requested dessert.
Now, you can try this key lime pie cupcake recipe for yourself! Follow the directions below to create a super addicting summer dessert. So good, actually, that you may just crave this treat all year ’round.
First things, first: gather your baking materials. Here are the items you will need to bake and decorate your key lime pie cupcakes. Feel free to click on any of the links to shop my favorite picks!
- Rolling pin
- Mixing bowl
- Flour sifter/sieve
- Handheld or stand mixer with the whisk attachment(s)
- Cupcake liners
- Cupcake tin (3)
- Fruit zester
- Double boiler and small saucepan
- Food-safe thermometer
- Cooling rack
- Piping bag and tip (depending on personal preference)
- Wax paper
Key Lime Pie Cupcakes Recipe
Take a look at my video tutorial first, for a visual idea of the baking process. Then, check out the written instructions for more in-depth recipe details.
And, if you’re not baking today, feel free to print this recipe or save it to Pinterest using the pins at the bottom!
Key Lime Pie Cupcakes
Graham Cracker Crust
- 1½ sleeves graham crackers, crushed
- 6 tbsp butter, melted
- ⅓ cup sugar
- 1 tsp salt
- 2½ cups all-purpose flour
- 2 tsp baking powder
- 1 tsp baking soda
- 2 cups white sugar
- ¾ cups butter, room temp
- 2 large eggs, room temp
- 2 tsp vanilla
- 2 cup milk, room temp
Key Lime Curd
- ¾ cup white sugar
- ½ cup key lime juice
- 2 tbsp lime zest
- 5 egg yolks
- 2 tbsp water, cold
- 1 pouch gelatin (approx. 2½ tsp)
- ¼ cup butter
Key Lime Buttercream
- 1½ cup butter, room temp
- ½ cup shortening
- 7-8 cups powdered sugar
- 1 tbsp lime zest, plus more for garnish
- 3½ tbsp key lime juice
- ½ tsp vanilla
- 2 limes, large
- 1 cup sugar, plus more for dusting
- 1 cup water
Graham Cracker Crust
- Line three muffin tins with paper cupcake liners, and preheat the oven to 350°F.
- Place the graham crackers into a ziplock bag, and use a rolling pin to crush them into fine pieces. There shouldn't be any large chunks remaining.
- In a mixing bowl, combine the graham cracker crumbs, melted butter, sugar, and salt. At first, the butter may stick to the crumbs in clumps, but keep stirring until the mixture is fully amalgamated. After a bit of mixing, it will resemble wet sand.
- Using your handy bar muddler, press a large spoonful of crumbs into each lined well of the muffin tin. Tamp down well, creating a nice, solid graham cracker crust.
- Bake the crusts for 7-8 minutes. They will be slightly golden brown when finished. Set aside and let cool while you prepare the cupcake batter.
- Into a medium-sized bowl, sift the flour, baking powder, and baking soda. Set aside.
- Beat the softened butter and sugar together on high for a few minutes, until the mixture is fluffy and light.
- Into the bowl of your mixer, add the room temperature eggs and vanilla. Beat again until everything is combined.
- Dump about a third of the flour mixture into the wet ingredients, and then pour in a third of the milk. Use a spatula to stir the batter until it just begins to come together. Repeat the process twice more, alternating between flour and milk. Stir carefully, distributing all the ingredients well, but taking care not to overmix the batter.
- Using a quarter-cup sized measure, portion the batter evenly among the lined muffin tins. Remember, the graham cracker crust should be baked before adding the cupcake batter.
- Place your cupcakes in the preheated oven (350°F) and bake for 28 minutes. Refrain from opening the oven prematurely, as letting the heat out can cause the cupcakes to deflate before forming enough structure to form a pretty domed top. When the timer is finished, use a toothpick to check for doneness. Moist crumbs are okay, but no wet batter should remain. If the cupcakes aren't fully cooked, let them bake for a few more minutes, testing again, before removing from the oven.
- Let the cupcakes cool in their tins for about ten minutes, then gently release to a cooling rack. Let them fully cool before moving on to the next steps. If you need to store the cupcakes overnight, do so in a covered container at room temperature.
Key Lime Curd
- Bring some water in a small pan to a simmer, and place your double boiler overtop.
- Combine the sugar, lime juice, lime zest, and egg yolks in the double boiler, and whisk to dissolve the sugar. Continue stirring, constantly, until the temperature passes 140°F. This will ensure the egg yolks are properly cooked, and eliminate any chance of obtaining a food-borne illness. Then, continue stirring until the mixture starts to thicken, a few minutes more.
- In a small bowl, add the cold water and pour in the gelatin. Let it sit for a few minutes to "bloom."
- Remove the curd mixture from the heat and add in your butter and bloomed gelatin. Whisk everything together until the butter has melted and gelatin is fully dissolved.
- Let this curd cool to room temperature, first, and then in the refrigerator. It will continue to thicken as the temperature drops.
- Using a melon baller or cupcake corer, remove the centers of your cupcakes. Keep the scraps in a separate container - we don't waste any of the good stuff.
- Next, add the cooled and thickened curd to a piping bag. Fill each cored cupcake center with the curd.
- Then, press a scoop of cake back over the curd hole. These extra cake bits will likely bulge over the top of the rest of the cupcake, which is fine. When we pipe the buttercream, this extra domed shape will help add some pretty height to the icing.
Key Lime Buttercream
- Add your softened butter and shortening to the bowl of your mixer and combine.
- Slowly add powdered sugar to the butter, one cup at a time, mixing and scraping down the bowl in between each new addition.
- To the buttercream, add in the lime juice and zest, as well as the vanilla. Mix well, and test the taste, adding more juice or vanilla if you'd prefer. This buttercream is best with a bright zing of key lime flavor, so don't hold back if you think it needs a bit more.
- Next, insert a star or rosette tip of your choosing into a piping bag, and fill it with your delicious buttercream. In a circular motion, apply buttercream to the cupcake, starting at the outer edge, moving up and in with steady pressure on the bag.
- Sprinkle on to the buttercream some extra lime zest for a zingy, finishing touch.
Candied Lime Slices
- Start off by setting a pan of water on the stove to boil.
- Cut the limes into thin slices, and then half or quarter each slice.
- Drop the lime slices into your pan of boiling water. Let them cook for two minutes. Then, strain them into a bowl of ice-cold water, reserving the boiling water. If you accidentally strain out the water, it's okay - you'll just have to reboil another pot. 🙂
- Stir the sugar back into the boiling water, and let it dissolve.
- Then, add your lime slices into the simmering sugar water. Let them cook for about 15 minutes, or until the piths (the white parts of the lime) are translucent.
- Remove the lime slices to a cooling rack. I suggest you place some tin foil underneath the rack for easy cleanup - these slices get very sticky as they dry!
- Once the lime slices are mostly dried, toss them in some sugar and let them set on a sheet of wax paper.
- Top each one of your cupcakes with a delicious candied lime slice and enjoy!
One bite of these key lime cupcakes will transport you directly to the beach! Grab some sunscreen and your swimsuit to finish out the experience.
Don’t forget to find me on Instagram so we can keep in touch, and be sure to tag me in any photos you post of your key lime cupcakes! I love seeing your kitchen creations!
If you’re looking for another great cupcake idea, check out my beloved Mocha Cupcakes with Chocolate Espresso Buttercream! These are my most requested cupcake, and a personal fave if you want something decadent-ly chocolate!
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Thanks for reading!
Addicted to Pinterest, like me? Pin the image below to save this recipe for later or show it to your friends. After all, sharing is caring. 😉