We all know about Key Lime Pie, but this key lime cake will give your favorite pie recipe some stiff competition. The cake itself is super moist and filled with fresh lime flavor. Then it gets soaked in a simple lime syrup and topped with Whipped Cream and lime zest.
What’s even better is that it’s a shortcut recipe that’s crazy easy to make because the recipe starts with a cake mix. Then the lime flavor is fresh and tangy (but never sour) because we’re using fresh limes.
I know a lot of key lime cake recipes use jello for the lime flavor, but I wanted to make a key lime cake without gelatin in it. Spoiler alert – This recipe used actual limes! If you don’t have key limes on hand, you can also use regular limes.
Citrus desserts are a must in the summertime, and this key lime cake (inspired by Key Lime Pie), is a favorite. We also love Lemon Bundt Cake, and Lime Sheet Cake when we need a citrus fix!
Why we think you’ll love it:
- Super Easy. This recipe uses a boxed cake mix, making it perfect for even the most beginner bakers.
- Tangy and Sweet. The flavor combination is the perfect balance of the tart key limes and sweet cake.
- Incredibly Moist. This cake has a tender, moist crumb that stays fresh and delicious.
Key Lime Cake Ingredients
Cake
- Cake mix (1 box, 15.25 ounce – vanilla, yellow, or white) – The easy shortcut base that keeps the cake soft and fluffy. Be sure to use only the cake mix powder in this recipe.
- Vegetable oil (½ cup) – Adds moisture so the cake stays tender. You can also use canola oil or melted coconut oil.
- Eggs (3 large) – Help bind the batter and give the cake structure and richness.
- Sour cream (¾ cup) – Makes the cake extra moist with a subtle tang that pairs perfectly with lime. Plain Greek yogurt can be used instead.
- Lime zest (2 tablespoons) – Packs in that bright citrus flavor and aroma. See how to zest citrus for tips.
- Freshly squeezed lime juice (⅓ cup) – Brings the tart, tangy punch that makes this cake shine. You’ll need about 2-3 Persian limes or 6-7 key limes.
Syrup
- Lime juice (3 tablespoons) – Soaks into the warm cake for extra flavor. You will need 1-2 Persian limes or 3-5 key limes.
- Sugar (3 tablespoons) – Sweetens the syrup and balances the tart lime.
Topping
- Whipped topping or whipped cream (2 cups) – Light and fluffy topping that keeps the dessert refreshing instead of heavy. You can use store-bought Cool Whip or make Homemade Whipped Cream.
- Lime zest (1 tablespoon) – A finishing touch of color and citrus zing that makes the cake look and taste extra fresh.
- Optional– garnish with lime slices
How to Make Key Lime Cake
Key Lime Cake
PREP. Preheat the oven to 350°F (or 325°F if using a glass pan). Grease and flour the bottom and sides of a 9×13-inch pan.
WHISK. Add the cake mix, eggs, sour cream, oil, lime juice, and lime zest to a large mixing bowl. Beat with an electric mixer on medium speed until smooth.
BAKE. Pour the batter into the prepared cake pans and bake for 27-32 minutes or until an inserted toothpick comes out clean, and if you give the pan a gentle nudge the cake doesn’t wobble in the middle.
COOL. Remove from the oven and allow to cool on wire racks.
Lime Syrup
HEAT. In a small saucepan over low heat, add the lime juice and sugar. Heat until the sugar dissolves while gently stirring.
BRUSH. When the cake is out of the oven, take a small pastry brush or a spoon and brush/drizzle the syrup over the top.
Topping
TOP. Spread the whipped topping over the top of the cooled cake. Then sprinkle with lime zest.
SERVE. Cut into slices and serve.
Kristyn’s Recipe Tips
- You can use either key limes or Persian limes to make this recipe.
- Use store-bought whipped topping or make homemade whipped cream.
- If you want the cake to be green, stir in a few drops of food coloring.
- Make a key lime layered cake by using two round cake pans (8-inch or 9-inch) and bake at 350° for about 22-25 minutes. Cool. Apply lime curd on one cake round and place the other cake round on top.
- Feel free to use Cream Cheese Icing in place of whipped cream.
Easy Key Lime Cake Recipe
Ingredients
Key Lime Cake
- 1 (15.25-ounce) box cake mix , vanilla, yellow or white
- ½ cup vegetable oil
- 3 large eggs
- ¾ cup sour cream
- 2 tablespoons lime zest
- ⅓ cup freshly squeezed lime juice
Key Lime Syrup
- 3 tablespoons lime juice
- 3 tablespoons sugar
Topping
- 2 cups whipped topping, or whipped cream
- 1 tablespoon lime zest
Instructions
Key Lime Cake
- Preheat the oven to 350°F (or 325°F if using a glass pan). Grease and flour the bottom and sides of a 9×13-inch pan.
- Add the cake mix, eggs, sour cream, vegetable oil, lime juice, and lime zest to a large bowl. Beat with an electric mixer until smooth.
- Pour the batter into the prepared pan and bake for 27-32 minutes or until an inserted toothpick comes out clean and if you give the pan a gentle nudge the cake doesn’t wobble in the middle.
- Remove from the oven and allow to cool.
Lime Syrup
- In a small saucepan over low heat add the lime juice and sugar. Heat until the sugar dissolves while gently stirring.
- When the cake is out of the oven, take a small pastry brush or a spoon and brush/drizzle the syrup over top.
Topping
- Spread the whipped topping over top of the cooled cake. Then sprinkle with lime zest.
- Cut into slices and serve.
Notes
- You can use either key limes or Persian limes to make this recipe.
- Use store-bought whipped topping or make homemade whipped cream.
- If you want the cake to be green, stir in a few drops of food coloring.
- Make a key lime layered cake by using two round cake pans (8-inch or 9-inch) and bake at 350° for about 22-25 minutes. Cool. Apply lime curd on one cake round and place the other cake round on top.
- Feel free to use Cream Cheese Icing in place of whipped cream topping.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Recipe FAQ
While both can be used, Key limes offer a more aromatic and slightly less acidic flavor, which provides a distinctive, floral essence to baked goods. Persian limes, being the more common variety, have a sharper, tart flavor and are much easier to juice due to their size and lack of seeds.
You can prepare the cake and the lime syrup up to 2 days ahead of time. Store the cooled cake, uncovered, at room temperature, and keep the syrup in an airtight container in the fridge. When you’re ready to serve, warm the syrup, brush it over the cake, and add the whipped topping and zest.
The unfrosted cake can be wrapped tightly and frozen for up to 3 months. Once topped with whipped cream, freezing is not recommended.
Store any leftover cake in an airtight container in the refrigerator for up to 3-4 days.
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This recipe was originally published July 2018.
Edible, but bland. Not near enough lime, or for that matter, any other taste. Even used homemade whipped cream for it. I think it could have used the lime gelatin. Not just for color, but taste.
Will the recipe make two 8 or 9 inch layers
This recipe is for a 9×13 pan, but you could also bake in two 9 inch round cake pans and layer.
Guests loved the cake with the modifications posted before. I brushed half of the lime syrup on the bottom of the cake and left it overnight before turning it over. In my frig was about 2/3 cream cheese frosting so I added it to the leftover lime syrup, warmed it up and poured it over the Bundt cake once slightly cooked. Even today those guests expressed how delicious the cake was-it’s definitely a keeper.
What do you think about adding lime gelatin to the batter!
Just took it out of the oven since I’m having company tomorrow but added an extra egg and a large lime jello to this recipe using white cake mix. It took exactly 36 minutes to bake and looks beautiful. I will give an update after we have tasted it; I’m excited!!!!!
Guests loved the cake with the modifications posted before. I brushed half of the lime syrup on the bottom of the cake and left it overnight before turning it over. In my frig was about 2/3 cream cheese frosting so I added it to the leftover lime syrup, warmed it up and poured it over the Bundt cake once slightly cooked. Even today those guests expressed how delicious the cake was-it’s definitely a keeper.
I used white cake mix, and it was so easy to make and the flavor was amazing! Thank you for the great recipe!
Light and delicious! Love citrus flavored dessert.
This cake is the perfect summer cook out dessert! It’s beyond delicous and makes it easy to feed a crowd!
Thank you for this! Exactly what I was looking for. I’m using it to make key lime cupcakes with the mini key limes . The only difference is I made some Italian Meringue Buttercream-coconut flavored icing to swirl on top. Beach/Tropical theme birthday.
What a fun treat to make for a tropical themed birthday! The coconut flavored icing sounds heavenly! Thanks for sharing what you do!
The lime syrup makes the cake moist and delicious. The simple cream topping was a perfect pair to the cakes flavor.
A quick cool dessert with a hint of lime. Very refreshing.
We love key lime, just as much as we like lemon. I love mixing it up & alternate between the two cakes. It’s nice & fluffy!
The perfect flavor of citrus in such a yummy textured cake. Thank you for always having the BEST recipes. This is a new family favorite!
So easy to make and tasted really amazing! Thank you so much for this key lime cake recipe, will surely have this again! Fam really loves it! Well done!
I am a huge fan of anything Key Lime Pie! This cake did not disappoint! So moist and full of that delicious key lime flavor.
We have made this a few times this summer. It’s always so refreshing & can feed a crowd.
Can you do this in bundt pan?
Yes you sure can! Just make sure you don’t overfill the bundt pan – leave at least 1/2 inch of empty space from the top. Also – you will need to adjust your cooking time. Bundt cakes typically take about 40-45 minutes to bake so I would check it at 40 minutes by inserting a toothpick into the center to see if it comes out clean. If it does not come out clean then bake it for 5-10 more minutes and check again. Hope this helps!
In the list of ingredients for key lime cake you dont have oil- in instructions you say add 1/2 cup oil.
I caught it- but didnt add. We’ll see how it turns out. ?
Yes, sorry..had it in the instructions, but forgot the ingredient list, so thank you for catching that!! Uh, oh..hope it’s ok 🙂
This looks absolutely delicious! A bit difficult for me to make as a beginner but I think its worth a try!
Totally worth a try 🙂 You can do it! You will love it!
yes it was so good
I made this cake and loved the flavor. However, the cake itself was very dry. Any ideas why? Is it because there is no oil?
Thank you
The lime juice makes up the liquid. I am not sure?? It hasn’t been too dry for us, so really I’m not sure what happened. I wish I could be more help. I’m sorry. I appreciate you making it 🙂
In the intro she says they use 1/2 C. oil, but it’s not included in the ingredients list or directions. That’s probably the problem…
Yes, sorry..I need to add that. I had it in the paragraph, but forgot it in the ingredients. You add 1/2 cup oil, when mixing the ingredients in step 2. Sorry about that 🙂
Does the cake need to be completely cooled before you put the lime syrup on?
I mostly cool the cake before putting the lime syrup on. You’ll want to for sure make sure the cake is cooled before putting the whipped topping o too.
love key lime flavors, cake too, so thank you and thank you for these other links too!
You are so welcome!! Thank you for stopping by!
Which flavor cake mix did you use?
I am definetely making this soon!
Love your blog!
You could do either vanilla, white, or yellow cake mix. I think mine was yellow cake mix. Any of those taste great 🙂 Hope you try it soon!