Mocha Cake with Kahlua Buttercream is a fluffy and moist coffee-flavored cake that’s just as irresistible as it sounds. The whole thing is smothered in rich and creamy coffee buttercream spiked with Kahlua liqueur. Truly a cake for coffee lovers!

A slice of mocha cake frosted with Kahlua buttercream on a white plate next to a fork.

Easy Mocha Cake With Kahlua Buttercream Frosting

The second I snuck a taste of the cake batter for this decadent mocha cake, I knew I was onto something great. It tasted just like coffee ice cream!

I’d adapted my favorite moist vanilla cake recipe using coffee in place of milk and amped up the flavor with espresso powder. The flavor was deep, intense, and everything I’d hoped it would be.

The cake itself came out unbelievably moist and tender, with rich coffee flavor throughout. If you’ve ever had a mochaccino before, you’ll know that mocha is a sort of chocolatey coffee vibe. This mocha cake ticks every box, topped with the most ridiculously creamy buttercream spiked with Kahlua coffee liqueur.

Why You’ll Love This Cake Recipe

Coffee, Kahlua, and cake: what’s not to love? Besides, well… everything, here are the top reasons you’ll be crazy about this mocha cake with Kahlua frosting:

Quick and easy. This sheet cake recipe comes together in a single bowl and bakes up quickly. Plus, frosting your cake is a breeze!
A coffee lover’s dream. The espresso flavors in this mocha cake are quite intense. If coffee is your thing, this cake is right up your alley! The crumb is rich and buttery, enhanced with espresso powder and brewed coffee.
Kahlua frosting. Then, there’s the creamy Kahlua buttercream frosting, filled with even more espresso flavor and spiked with coffee liqueur. Heaven!

Key Ingredients

In addition to your usual baking staples like flour, eggs, and sugar, this mocha cake gets its distinct flavor from a few key ingredients, mentioned below. Be sure to scroll to the recipe card for the full recipe amounts and details.

Oil – Almost all of my cakes and cupcake recipes trade butter for vegetable oil. The cake comes out super soft and moist since the oil stays liquid at room temperature.
Sour Cream – Secret weapon number 2 for ultra-moist cakes. You don’t really taste the sour cream in the final cake, but it adds loads of moisture to the crumb.
Espresso Powder – Make sure to use powder and not granules. If you can’t find espresso powder, finely ground coffee will also work. You can find this product near the instant coffee in the grocery store.
Brewed Coffee – I used cold brew coffee in this recipe as I almost always have it in my fridge. Otherwise, brew a strong batch of instant coffee or espresso.
Butter – I recommend using unsalted butter. If you’re using salted butter, consider leaving out any added salt so that the frosting doesn’t come out salty.
Kahlua – I flavor this coffee buttercream with additional espresso powder, a dash of vanilla, and a splash of Kahlua coffee liqueur.

What Is Kahlua?

Kahlúa is a brand of Mexican coffee liqueur made from rum, sugar, and arabica coffee beans. It adds an “adult” coffee-flavored twist to the frosting in this recipe. If you’d prefer to make your frosting without alcohol, I’d recommend this coffee frosting instead.

How to Make a Mocha Cake

We’ll start by preparing this super-easy mocha cake batter. I bake this cake as a sheet cake in a 9×13-inch baking pan. You could also use round pans to make a layer cake if you prefer. See further on for adjusted baking times for different pan sizes.

Combine the wet ingredients. While your oven preheats, beat the sugar together with oil, eggs, and vanilla, followed by the sour cream.
Add the dry ingredients. Next, you’ll add the flour with the other dry ingredients, alternating with the brewed coffee until the batter is well combined. Be careful that you don’t overmix, though.
Bake. Transfer the cake batter to your 19×13-inch pan, and bake at 350ºF for 28-32 minutes. Afterward, take the cake out of the oven and leave it to cool completely before frosting.

Make the Frosting

I debated over the frosting for this mocha cake. I’d first planned to use my favorite chocolate buttercream frosting to really play up the chocolate and coffee flavors. Then, I settled on a coffee buttercream like the one I use in my chocolate mocha cake with the idea to bring Kahlua into the mix. And WOW. This Kahlua coffee frosting came out amazing! It was also very easy to make:

Beat the butter. I like to use cold butter straight from the fridge. It takes some extra whipping to get the butter soft but trust me, it’s worth it! Cut the butter into pieces and then give it a good whip in your mixer. After about 3-5 minutes, it should be fluffed and lighter in color.
Combine and whip. Add half the powdered sugar, followed by the espresso powder. Once that’s well mixed, add Kahlua, vanilla, and finally, the remaining powdered sugar, followed by heavy cream. Beat the frosting, gradually increasing the speed, until it’s smooth and fluffy.
Frost the cake. Spread your Kahlua buttercream all over your cooled mocha cake. At this point, you can cut into the finished cake as is, or, check out my ideas below for some easy ways to decorate a mocha cake.

Recipe Tips

Follow these bonus tips for an ultra-moist and fluffy, perfect mocha cake with the creamiest frosting:

Don’t overmix the cake batter. Overworking the batter deflates the air bubbles needed for a light and fluffy cake. Your mocha cake will end up dense and tough, and no one wants that!

Make the frosting a day ahead. Not only is it ready to go with a quick whip the following day, but this spiked expresso frosting tastes even better once the coffee and Kahlua flavors have had the chance to develop overnight.

Adjust the thickness of the frosting by adding additional powdered sugar or heavy cream, one spoonful at a time, to either thicken or thin out the consistency (respectively).

A fork stuck into the corner of a slice of mocha cake frosted with Kahlua buttercream.

Can I Make This As a Layer Cake Instead?

I’m all about the convenience of a sheet cake, but you can definitely make this mocha cake as a layer cake instead. This recipe makes enough batter to fill three 8-inch round cake pans or two 9-inch round pans (though the layers in a 9-inch cake will be quite thin).

For an 8” 3-layer cake, divide the batter evenly between three round pans and bake at 350ºF for about 20-24 minutes. See my mocha almond fudge cake for a similar variation.
For a 9” 2-layer cake, fill two round pans and bake at 350ºF for about 28-32 minutes.

Note that you will also need to double the frosting recipe for a two- or three-tiered layer cake. Any leftover frosting will keep in the fridge, see below for storage details.

More Decorating Ideas

Once frosted, this mocha sheet cake is like a blank canvas that you can decorate in so many ways. I like to top my cake with chocolate sprinkles, or shaved or chopped chocolate. Or, try drizzling over some pourable ganache.

You can be fancy or keep things simple when decorating, it’s totally up to you. If you’d like to dress up your mocha cake, go ahead and get creative with piping extra frosting. I have helpful tutorials on how to use a piping bag and how to use piping tips that walk you through how to create perfect piping swirls and more.

If you’d like to change up the frosting for your mocha cake, other good options are chocolate whipped cream or this chocolate Swiss meringue buttercream.

A slice of frosted mocha cake on a white plate next to a fork, with a corner missing.

How to Store a Frosted Cake

This frosted mocha cake stays fresh and moist when stored at room temperature for a couple of days. Make sure that the cake stays covered and airtight for storage. I don’t recommend storing frosted cakes in the fridge unless it’s absolutely necessary, as they tend to dry out. However, here’s the best way to refrigerate and freeze your cake if needed:

Fridge: If your kitchen is particularly warm, keep your cake covered in the fridge and take it out to serve at room temperature.
Freezer: I prefer to freeze my cakes before they’re frosted, however, this mocha cake is fine to freeze after it’s been frosted, too. Wrap the baked and cooled cake tightly in a double layer of plastic wrap, and freeze it for up to 3 months. Thaw the cake in the fridge overnight, and bring it to room temperature before serving.
Frosting: Leftover Kahlua buttercream frosting can be kept airtight at room temperature for 1-2 days, or stored in the fridge for up to 1 week. You can also freeze buttercream for up to 3 months, and defrost it in the fridge. Give the frosting a fresh whip before using.

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