Fluffy and zesty, these Key Lime Cupcakes are a citrusy burst of sunshine in every bite. With a perfectly balanced tart-sweet flavor and a rich, creamy lime frosting, I find they’re an ideal treat for warm-weather celebrations or anytime I crave something refreshing and fun.
Why You’ll Love This Recipe
I love how these cupcakes bring together the light, airy texture of classic vanilla cake with the bright zing of key lime. The addition of sour cream gives the crumb extra moisture, while the fresh lime juice and zest add a pop of citrus in every bite. Topped with a silky cream cheese and lime frosting, they’re indulgent yet not too heavy. Whether I’m making them for a picnic, birthday party, or just to treat myself, these cupcakes always disappear fast.
Ingredients
(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)
For the Cupcakes:
1 1/2 cups all-purpose flour
1/2 teaspoon baking powder
1/4 teaspoon baking soda
1/4 teaspoon salt
1/2 cup unsalted butter, softened
1 cup granulated sugar
2 large eggs
1/4 cup sour cream
1/4 cup fresh key lime juice
1 tablespoon key lime zest
1 teaspoon vanilla extract
1/3 cup whole milk
For the Frosting:
1/2 cup unsalted butter, softened
4 oz cream cheese, softened
2 tablespoons key lime juice
1 teaspoon key lime zest
2 1/2 cups powdered sugar
Pinch of salt
Directions
I start by preheating the oven to 350°F (175°C) and lining a 12-cup muffin pan with cupcake liners.
In a medium bowl, I whisk together the flour, baking powder, baking soda, and salt.
In a large mixing bowl, I cream the butter and sugar until it’s light and fluffy.
I beat in the eggs one at a time, then mix in the sour cream, key lime juice, zest, and vanilla extract.
Next, I gradually add the dry ingredients to the wet mixture, alternating with the milk. I mix just until everything is combined.
I fill each cupcake liner about 2/3 full with batter and bake for 18–22 minutes, until a toothpick inserted in the center comes out clean.
Then I let the cupcakes cool in the pan for 5 minutes, then transfer them to a wire rack to cool completely.
For the frosting, I beat the butter and cream cheese together until smooth, then add the key lime juice, zest, and a pinch of salt. I slowly mix in the powdered sugar until the frosting is fluffy and spreadable.
Once the cupcakes are cool, I frost them using a piping bag or a spatula. I sometimes garnish with a little lime zest or a small lime slice for a pretty finish.
Servings and timing
This recipe makes 12 cupcakes.
Prep Time: 20 minutes
Cook Time: 20 minutes
Total Time: 40 minutes
Calories: Approximately 320 kcal per cupcake
Variations
I sometimes use regular limes if key limes aren’t available—the flavor is still delicious.
For a tropical twist, I like to add a bit of shredded coconut to the batter or as a topping.
If I want more color, I add a drop of green food coloring to the frosting.
I’ve also swapped the cream cheese frosting for a whipped cream topping to make them lighter.
To make mini cupcakes, I reduce the baking time to about 10–12 minutes.
Storage/Reheating
I store the cupcakes in an airtight container in the refrigerator for up to 4 days. Before serving, I let them sit at room temperature for about 20 minutes so the frosting softens. I don’t recommend reheating these since they’re best enjoyed fresh or chilled.
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FAQs
What’s the difference between key limes and regular limes?
Key limes are smaller, more aromatic, and slightly more tart than regular Persian limes. They give these cupcakes a more intense citrus flavor, but regular limes work in a pinch.
Can I make these cupcakes ahead of time?
Yes, I often bake the cupcakes a day ahead and store them unfrosted. I prepare the frosting fresh the day of serving and decorate right before.
Can I freeze the cupcakes?
I can freeze the unfrosted cupcakes for up to 2 months. I wrap them tightly in plastic wrap and store them in a freezer-safe container. When ready to enjoy, I thaw them at room temperature and then frost.
Why is my frosting too runny?
If the frosting is too soft, it may be due to warm ingredients or overmixing. I pop it in the fridge for 10–15 minutes, then beat it again to firm it up.
Can I make these gluten-free?
Yes, I swap the all-purpose flour with a gluten-free 1:1 baking blend. I make sure the blend includes xanthan gum for structure.
Conclusion
These Key Lime Cupcakes are a sweet, zesty treat that I love making for just about any occasion. They’re easy to whip up, pack a citrusy punch, and never fail to impress with their light texture and vibrant flavor. Whether I’m baking for a party or just because, they always bring a bit of sunshine to my day.
📖 Recipe:
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Key Lime Cupcakes
- Total Time: 40 minutes
- Yield: 12 cupcakes
- Diet: Vegetarian
Description
Fluffy and zesty Key Lime Cupcakes with a citrusy burst of key lime in every bite, topped with creamy lime cream cheese frosting. Perfect for warm-weather celebrations or anytime you want a refreshing treat.
Ingredients
1 1/2 cups all-purpose flour
1/2 teaspoon baking powder
1/4 teaspoon baking soda
1/4 teaspoon salt
1/2 cup unsalted butter, softened
1 cup granulated sugar
2 large eggs
1/4 cup sour cream
1/4 cup fresh key lime juice
1 tablespoon key lime zest
1 teaspoon vanilla extract
1/3 cup whole milk
For the Frosting:
1/2 cup unsalted butter, softened
4 oz cream cheese, softened
2 tablespoons key lime juice
1 teaspoon key lime zest
2 1/2 cups powdered sugar
Pinch of salt
Instructions
- Preheat the oven to 350°F (175°C) and line a 12-cup muffin pan with cupcake liners.
- In a medium bowl, whisk together the flour, baking powder, baking soda, and salt.
- In a large mixing bowl, cream the butter and sugar until light and fluffy.
- Beat in the eggs one at a time, then mix in the sour cream, key lime juice, zest, and vanilla extract.
- Gradually add the dry ingredients to the wet mixture, alternating with the milk. Mix just until combined.
- Fill each cupcake liner about 2/3 full with batter and bake for 18–22 minutes, until a toothpick inserted in the center comes out clean.
- Let the cupcakes cool in the pan for 5 minutes, then transfer them to a wire rack to cool completely.
- To make the frosting, beat the butter and cream cheese together until smooth. Add the key lime juice, zest, and a pinch of salt.
- Slowly mix in the powdered sugar until the frosting is fluffy and spreadable.
- Once the cupcakes are cool, frost them using a piping bag or spatula. Garnish with lime zest or a lime slice if desired.
Notes
Regular limes can be used if key limes aren’t available.
For added tropical flavor, mix shredded coconut into the batter or sprinkle on top.
A drop of green food coloring can be added to the frosting for extra color.
For a lighter topping, use whipped cream instead of cream cheese frosting.
To make mini cupcakes, bake for 10–12 minutes.
Store in an airtight container in the fridge for up to 4 days. Let sit at room temperature before serving.
- Prep Time: 20 minutes
- Cook Time: 20 minutes
- Category: Dessert
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 1 cupcake
- Calories: 320
- Sugar: 30g
- Sodium: 150mg
- Fat: 16g
- Saturated Fat: 10g
- Unsaturated Fat: 5g
- Trans Fat: 0g
- Carbohydrates: 40g
- Fiber: 0.5g
- Protein: 3g
- Cholesterol: 55mg
