A coconut lime cake that tastes like a tropical getaway—no passport required.
This Coconut Lime Sheet Cake is like a slice of summer in every bite. The combo of zesty lime and sweet coconut gives it a bright, tropical flavor that’s hard to resist. With a fluffy texture, easy cake mix base, and toasted coconut lime frosting, it’s the kind of dessert that feels both refreshing and indulgent—perfect for warm-weather parties or anytime you need a taste of the tropics.
Why You’ll Love This Recipe
Made with a simple white cake mix and a few flavor upgrades.
Bright coconut lime flavor in every bite.
Toasted coconut adds texture and sweetness.
The lime zest and juice give the frosting a fresh, tangy twist.
Perfect for spring and summer parties or casual gatherings.
Easy to make but looks and tastes bakery-worthy.
Ingredient Notes
White Cake Mix – Use your favorite brand; this creates a soft, fluffy base that’s easy to upgrade.
Buttermilk – Adds richness and tang, balancing the sweetness and giving the cake a tender crumb.
Coconut Extract – A little goes a long way to bring out that tropical coconut flavor.
Lime Zest & Juice – Fresh is best! The zest adds bold citrus flavor, while the juice brightens the frosting.
Shredded Sweetened Coconut – Fold it into the batter for texture and toast some for a golden, nutty topping.
Salted Butter – Helps balance the sweetness in the frosting while keeping it rich and creamy.
Heavy Cream – Adds fluff and smoothness to the frosting—adjust to your preferred consistency.
Before You Bake
Do I need to toast the coconut? Toasting the coconut is optional but highly recommended—it enhances the flavor and gives the cake a light crunch on top.
Can I use canned coconut milk instead of buttermilk? Stick with buttermilk for the best texture. Canned coconut milk is too thick and may make the cake heavy.
Should I use fresh lime juice or bottled? Fresh lime juice and zest give the best flavor. Bottled juice can be dull and lack that bright citrus punch.
Cake Ingredients (Makes one 9×13-inch cake or two 8-inch rounds)
1 box white cake mix (15.25 oz)
¾ cup buttermilk
½ cup vegetable oil
3 large eggs
Zest of 1 lime
1 teaspoon coconut extract
½ teaspoon vanilla extract
½ cup sweetened shredded coconut
Frosting Ingredients
1 cup (2 sticks) salted butter, softened
3½ cups powdered sugar
Zest of 1 lime
2 tablespoons lime juice
1 teaspoon coconut extract
¼ cup heavy cream (add as needed for texture)
½ cup sweetened shredded coconut, toasted (toast for 2–3 minutes and let cool)
Instructions
Make the Cake:
Preheat the oven to 350°F. Grease and flour a 9×13-inch pan or two 8-inch round pans.
In a large bowl, mix together the cake mix, buttermilk, oil, eggs, lime zest, coconut extract, and vanilla. Stir until just combined—avoid overmixing.
Fold in the shredded coconut for a burst of texture in every bite.
Bake according to box directions, then let the cake cool completely before frosting.
Make the Frosting:
In a dry skillet over medium heat, toast the shredded coconut for 2–3 minutes or until golden and fragrant. Set aside to cool.
In a large bowl, beat the butter until smooth and creamy. Add lime zest, lime juice, and coconut extract.
Slowly mix in the powdered sugar. Add the heavy cream a tablespoon at a time until you reach a smooth, spreadable consistency.
Stir in ¼ cup of the toasted coconut.
Frost the cooled cake and finish with a sprinkle of the reserved toasted coconut on top for extra flavor and a pretty finish. Add additional sliced limes, if desired.
FAQ
Can I make this Coconut Lime Sheet Cake ahead of time? Yes! Bake the cake a day ahead and frost it before serving. It tastes even better after the flavors sit overnight.
Does this cake need to be refrigerated? If frosted, yes—store it in the fridge and let it come to room temp before serving. Without frosting, it can sit covered at room temperature for a day.
Can I make this into cupcakes? Absolutely. This recipe makes about 24 standard cupcakes. Bake at 350°F for 15–18 minutes.
Can I freeze the cake? Yes. Freeze the unfrosted cake tightly wrapped for up to 2 months. Thaw in the fridge before frosting.
What’s the best way to zest a lime? Use a microplane or fine grater and only zest the green layer—avoid the bitter white pith underneath.
Sprinkle of Fun
Make this Coconut Lime Sheet Cake the star of your backyard luau. Set the scene with tiki torches, grass skirts, and pineapple centerpieces, then serve tropical mocktails or coconut-flavored drinks in fun cups with mini umbrellas. Pair the cake with fruit kabobs or a Hawaiian BBQ spread. Spend the day playing island music, hosting a limbo contest, and handing out leis at the door. This cake makes the perfect dessert for guests to grab between hula hooping and dancing under the string lights.