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 (Âľ 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 (â…“ 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
- Âľ cup sour cream
- 2 tablespoons lime zest
- â…“ 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.Â
- 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.Â
- 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.