These key lime cupcakes are a delightful treat, balancing a zesty lime flavor with a fluffy texture. Perfect for any occasion, they are quick to prepare and family approved. You’ll fall in love with their refreshing taste, making them an ideal dessert to whip up today!
Table of Contents

Key Lime Cupcakes
Summary
Key lime cupcakes are a refreshing dessert bursting with citrus flavor. They’re light, fluffy, and topped with creamy lime buttercream frosting. Ideal for spring gatherings or any celebration, these cupcakes are sure to impress your family and friends.

Ingredients
For the Key Lime Cupcakes
- 6 tablespoons unsalted butter, at room temperature
- 3/4 cup sugar
- 6 tablespoons sour cream
- 1/2 teaspoon vanilla extract
- 1 1/2 teaspoons key lime zest
- 3 egg whites
- 1 1/4 cups all-purpose flour (163g)
- 2 teaspoons baking powder
- 1/4 teaspoon salt
- 4 tablespoons milk
- 4 tablespoons key lime juice
For the Lime Buttercream Frosting
- 3/4 cup butter
- 3/4 cup shortening
- 6 cups powdered sugar
- 3-4 tablespoons key lime juice
- 1 teaspoon lime zest
- 1/4 cup graham cracker crumbs
Instructions
Make the Key Lime Cupcakes
Start by preheating your oven to 350°F and lining a cupcake pan with liners. In a large bowl, beat the butter and sugar together until the mixture is light and fluffy, which will take about 3-4 minutes. Next, mix in the sour cream, vanilla extract, and key lime zest until everything is well combined.
Gradually add the egg whites in two parts, mixing well after each addition and scraping down the bowl as necessary. In another bowl, whisk together the flour, baking powder, and salt. Meanwhile, combine the milk and key lime juice in a small measuring cup.
Add half of the dry ingredients to the batter and mix until combined. Then add the milk mixture and mix again. Finally, add the remaining dry ingredients and mix until fully incorporated. Fill the cupcake liners about three-quarters full and bake for 15-17 minutes, or until a toothpick inserted comes out with a few crumbs. Allow the cupcakes to cool for 2-3 minutes in the pan before transferring them to a cooling rack.
Make the Lime Buttercream Frosting
In a large bowl, mix the butter and shortening together until smooth. Gradually add half of the powdered sugar and mix until the texture is smooth. Incorporate the key lime zest and 3 tablespoons of key lime juice, mixing until well combined. Then, add the remaining powdered sugar and mix until smooth, adjusting with more key lime juice if needed for your desired consistency.
Pipe the frosting onto the cooled cupcakes and press graham cracker crumbs around the edges of the frosting for that delicious crunch.
Notes
If you want an all-butter frosting, simply substitute the 3/4 cup shortening with an additional 3/4 cup butter. These cupcakes yield about 12 to 14 servings and can be prepped in just 15 minutes, with a cook time of 15-17 minutes. For storage, keep them in an airtight container at room temperature for up to 3 days. You can also use regular limes in place of key limes for zest and juice without sacrificing flavor.
FAQs
What ingredients do I need to make key lime cupcakes?
To make key lime cupcakes, you’ll need unsalted butter, sugar, sour cream, vanilla extract, key lime zest, egg whites, all-purpose flour, baking powder, salt, milk, and key lime juice.
How do I achieve the perfect key lime flavor in cupcakes?
To achieve the perfect key lime flavor, use fresh key lime juice and zest. Adjust the quantity to your taste preference for a more intense flavor.
Can I use bottled key lime juice for my cupcakes?
Yes, you can use bottled key lime juice, but fresh key lime juice and zest provide a brighter, more authentic flavor.
What is the best frosting for key lime cupcakes?
The best frosting for key lime cupcakes is lime buttercream frosting, made with butter, shortening, powdered sugar, key lime juice, and zest for a creamy finish.
How do I store leftover key lime cupcakes?
Store leftover key lime cupcakes in an airtight container at room temperature for up to 3 days to maintain their freshness.
Related Recipes to try
Conclusion
These key lime cupcakes are the perfect sweet treat to brighten your day. For more inspiration, check out delicious ideas on Pinterest. They’re easy to make and will leave everyone asking for seconds!

Key Lime Cupcakes
Equipment
- cupcake pan
- mixing bowls
- whisk
- Measuring cups
- mixer
- Spatula
- Piping bag
Ingredients
- 6 tablespoons unsalted butter at room temperature
- 3/4 cup sugar
- 6 tablespoons sour cream
- 1/2 teaspoon vanilla extract
- 1 1/2 teaspoons key lime zest
- 3 egg whites
- 1 1/4 cups all-purpose flour (163g)
- 2 teaspoons baking powder
- 1/4 teaspoon salt
- 4 tablespoons milk
- 4 tablespoons key lime juice
Lime Buttercream Frosting
- 3/4 cup butter
- 3/4 cup shortening
- 6 cups powdered sugar
- 3-4 tablespoons key lime juice
- 1 teaspoon lime zest
- 1/4 cup graham cracker crumbs
Instructions
- Preheat the oven to 350°F and line a cupcake pan with liners.
- Beat the butter and sugar together until light and fluffy, about 3-4 minutes.
- Mix in the sour cream, vanilla extract, and key lime zest until well combined.
- Gradually add the egg whites in two parts, mixing well after each addition.
- Whisk together the flour, baking powder, and salt in another bowl.
- Combine the milk and key lime juice in a small measuring cup.
- Add half of the dry ingredients to the batter, then the milk mixture, and finally the remaining dry ingredients.
- Fill the cupcake liners three-quarters full and bake for 15-17 minutes.
- Cool the cupcakes in the pan for 2-3 minutes before transferring to a cooling rack.
- For the frosting, mix butter and shortening until smooth, then gradually add powdered sugar.
- Incorporate key lime zest and juice, then add remaining powdered sugar.
- Pipe the frosting onto cooled cupcakes and press graham cracker crumbs around the edges.




