Guinness Chocolate Cake with Irish Buttercream – (Best Ever!)

Guinness Chocolate Cake with Irish Buttercream is your new not-so-secret weapon for winning St. Patrick’s Day—or any day that calls for a rich, chocolatey, frosting-laden moment of joy. From the first moist bite of cocoa-infused cake to the last silky swirl of Irish cream-spiked buttercream, this dessert brings the party in all the right ways. It’s fudgy, it’s fluffy, and it’s got a hint of Guinness that adds depth without overwhelming the sweetness.

Whether you’re baking for a crowd, your coworkers, or just treating yourself on a cozy night in, this Guinness Chocolate Cake with Irish Buttercream hits the sweet spot between indulgence and celebration. And guess what? You don’t have to be Irish to fall in love with this recipe. It’s perfect for anyone who loves a bit of decadence, a splash of whimsy, and desserts that make people go “Wait…did you make this from scratch?!”

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What is Guinness Chocolate Cake with Irish Buttercream?

Guinness Chocolate Cake with Irish Buttercream is a luscious layer cake that combines the dark, malty richness of Guinness beer with the deep flavor of cocoa, producing an incredibly moist, almost brownie-like chocolate cake. It’s not “beer-y” in the way a pint hits your palate, but the stout’s slight bitterness balances the sugar, intensifies the chocolate, and gives the cake a depth that regular cocoa cakes often lack. The frosting? Oh, honey—it’s not just buttercream, it’s Irish cream buttercream.

Think Bailey’s. Sweet, silky, with a grown-up twist that makes it taste like your favorite cozy café treat got dressed up for a fancy party. Add a glossy chocolate drip on top and some festive sprinkles or curls, and you’ve got a showstopper. This cake often pops up around St. Patrick’s Day, but I’m just going to say it—it deserves a spot at birthdays, dinner parties, and even Tuesday nights when you need something extra.

Reasons to Try Guinness Chocolate Cake with Irish Buttercream

First off, it’s ridiculously moist. Like “did someone inject this with pudding?” level moist. That alone should have you preheating your oven. But if you need more convincing, Guinness Chocolate Cake with Irish Buttercream brings a fun, grown-up flavor without requiring any fancy bakery skills. You don’t have to be a cake-decorating queen—this recipe even leans into the trendy “naked cake” look, so a rustic finish is not only okay, it’s encouraged.

The buttercream is creamy, rich, and super easy to whip together. If you’re used to box cake mixes or store-bought frostings, this recipe will make you feel like a pastry chef in your own kitchen. It’s also a perfect celebration cake that doesn’t feel overdone or cliché—whether you’re hosting a party or just want a dessert that sparks joy, this one’s it. And if you’ve got leftover Guinness? You’re one step closer to dinner with this Guinness beef chili or just kick back with a glass while the cake bakes. You’ve earned it.

Ingredients Needed to Make Guinness Chocolate Cake with Irish Buttercream

For the Guinness Chocolate Cake:

• 1 ¾ cups all-purpose flour
• 2 cups granulated sugar
• ¾ cup unsweetened cocoa powder
• 2 teaspoons baking soda
• ½ teaspoon baking powder
• 1 teaspoon fine sea salt
• ¾ cup sour cream or full-fat plain yogurt
• ½ cup vegetable oil
• 3 large eggs
• 1 teaspoon vanilla extract
• 1 cup Guinness beer

For the Irish Buttercream:

• 4 sticks unsalted butter, at cool room temp
• 6 cups powdered sugar, sifted
• ¼ cup + 2 tablespoons Irish cream liqueur (like Bailey’s)

For the Chocolate Drip (optional but highly recommended):

• 4 oz semisweet or bittersweet chocolate, chopped
• ½ cup heavy cream
• Optional: festive sprinkles or chocolate curls for topping

Instructions to Make Guinness Chocolate Cake with Irish Buttercream – Step by Step

Prepping Your Cake Pans Like a Pro

First things first: preheat that oven to 350°F. Then grease up two 8-inch round cake pans with a generous hand—don’t be shy, nobody wants a stuck cake. Pop a round of parchment paper in the bottom of each pan for insurance. If you’ve ever tried to flip a cake and lost half to the pan, you know this step is your best friend.

Mixing Dry Ingredients for That Rich Chocolate Flavor

In a large mixing bowl, whisk together your dry ingredients: flour, sugar, cocoa powder, baking soda, baking powder, and salt. This is your chocolatey foundation, so give it a thorough mix. Pro tip? Sift the cocoa if it looks clumpy—it’ll help avoid bitter pockets later. This step ensures even flavor and texture, giving you that fudgy, tender crumb we’re going for.

Whisking the Wet Ingredients – Yes, Including the Beer

In a separate bowl, whisk together the sour cream (or yogurt), oil, eggs, vanilla, and Guinness. This combo might look odd at first, but it’s magic. The Guinness adds richness and balances the sugar. Whisk until smooth—no lumps or eggy streaks.

Combining Wet and Dry – Gently Does It

Now pour the wet ingredients into the bowl of dry ingredients. Stir with a spatula or wooden spoon until it just comes together. No overmixing! A few streaks are fine. Overmixing activates gluten and can make the cake dense. And we’re going for moist, not muffin.

Baking the Cakes to Perfection

Divide the batter evenly between the two pans—eyeball it or use a scale if you’re precise. Pop them in the oven and bake for 35–40 minutes, or until a tester comes out clean. While they bake, cue up your favorite playlist or start cleaning up the chocolate explosion that probably happened on your counter.

Cooling and (Optional) Freezing for Easy Frosting

Let the cakes cool in their pans for about 30 minutes before turning them out onto a wire rack. Cool completely. If you’ve got time, freeze the layers while you make the buttercream—it makes assembly so much easier, especially if you’re not a pro-level froster.

Making the Irish Buttercream – Sweet, Creamy Bliss

Grab a large bowl and your electric mixer. Beat the butter until it’s light and fluffy—think whipped and pale. Then gradually add sifted powdered sugar (yes, sifting is annoying, but it’s worth it to avoid lumps). Pour in the Irish cream and beat on high until it’s smooth, creamy, and spreadable. Too thick? Add a splash more Irish cream. Too thin? Add a bit more sugar. You’re the boss here.

Assembling the Cake – Layering Like a Pro

Set one cake layer down on a stand or plate. Slather a generous amount of buttercream on top. This will be your filling, so don’t skimp. Add the second layer, flat side up. Now it’s time for a crumb coat—a super thin layer of frosting that seals in the crumbs. Use an offset spatula to smooth it out, then pop the cake into the fridge to firm up.

Final Frosting – Naked Cake or Not

Once chilled, use the remaining buttercream to finish frosting the cake. You can go full-coverage or stick with the trendy “naked cake” look. If you’re going for rustic elegance, focus the frosting on the top and let the sides peek through. Totally charming.

Chocolate Drip – Optional, but Come On

Now for the fun part. Place your chopped chocolate in a bowl. Heat the cream until just simmering (either on the stove or in the microwave), then pour it over the chocolate. Let it sit a few minutes, then stir until smooth. Let it cool a bit—too runny and it’ll slide right off your cake. Test a drip on the side of a glass if you’re unsure.

Gently pour a bit of the ganache onto the top of the chilled cake and smooth it toward the edges. Use a squeeze bottle or spoon to create elegant drips down the sides. Before it sets, add sprinkles, curls, or whatever toppings make you smile.

That’s it! You’ve made a Guinness Chocolate Cake with Irish Buttercream, step by step. And honestly? You nailed it.

What to Serve with Guinness Chocolate Cake with Irish Buttercream

This cake is a celebration all on its own, but if you want to take things to the next level, serve it with scoops of vanilla bean ice cream or a dollop of whipped cream. Got leftover Guinness? Use it to pair the cake with a glass of the same beer—it adds a cozy pub vibe. Hosting a full St. Patrick’s Day meal? Try serving this cake after a hearty Irish-inspired dinner like creamy coconut shrimp curry or shrimp orzo in lemon garlic sauce for a surprising twist. And for your green-themed table? Don’t forget a batch of green cookies. They make a great kid-friendly sidekick.

Key Tips for Making Guinness Chocolate Cake with Irish Buttercream

Don’t overmix your batter—once the wet hits the dry, a gentle stir is all it needs. Make sure your eggs and dairy are at room temperature for better blending and a smoother batter. Sift your powdered sugar and cocoa to avoid lumpy frosting or bitter bites. Chill your cake before frosting for fewer crumbs and cleaner lines. And finally, if your ganache is too runny, give it time. If it’s too thick, microwave it for 5–10 seconds. Test it before committing to the cake!

Storage and Reheating Tips for Guinness Chocolate Cake with Irish Buttercream

This cake keeps beautifully thanks to the Irish cream in the buttercream—it acts as a light preservative. Store it at room temperature for up to 3 days, covered with a cake keeper (not plastic wrap—that’s a frosting ruiner). If you live somewhere warm or humid, stash it in the fridge but let it sit out 30 minutes before serving for best texture. Want to freeze the layers? Wrap each (unfrosted) cake round in plastic wrap and foil, and freeze for up to a month. Thaw in the fridge overnight.

FAQs

Does this cake taste like beer?
Not really! The Guinness adds depth but doesn’t overpower. Think of it like adding coffee to chocolate cake—it enhances, not dominates.

Can I make this without alcohol?
You can swap the Guinness for coffee or even water in the cake. For the buttercream, sub Irish cream with heavy cream + a splash of vanilla.

What if I don’t have an electric mixer?
No worries—use a strong arm and a whisk. It’ll take more time but still works!

Can I make it gluten-free?
Try a 1:1 gluten-free flour blend. Just keep an eye on bake time as texture may shift slightly.

Is it okay to make the cake layers ahead?
Yes! Wrap them tightly and freeze until ready to assemble. Just be sure to let them thaw in the fridge before frosting.

Final Thoughts

Guinness Chocolate Cake with Irish Buttercream is everything a cake should be: rich, fluffy, flavorful, and just a little bit cheeky. It’s got the wow factor of a bakery cake but can be made right in your own kitchen, no professional gear required. Whether you’re baking for St. Patrick’s Day or just need a chocolate fix that doesn’t mess around, this cake has your back. With step-by-step guidance, you can pull off a showstopper dessert that looks as good as it tastes. And hey, while you’re here, why not check out other festive ideas like Shamrock Shake Pudding Cups or St. Patrick’s Day Sugar Cookie Bars? Now go grab that whisk—you’ve got cake to make.

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