Rich, chocolatey, and made with Guinness, this easy egg-free cake is perfect for St. Patrick’s Day.
Guinness Chocolate Cake with Chocolate Frosting: A Rich, Chocolatey St. Patrick’s Day Dessert
This style of cake has been on my bucket list to create for the blog. I love cooking with alcohol, and I really love cooking with Guinness around this time of year — it brings so much flavor and depth and works so well in both savory and sweet dishes. Guinness Chocolate Cake with Chocolate Frosting is truly next level — rich, chocolatey, with the perfect crumb and finished with a classic chocolate butter frosting. I made my partner bring the cake into his work after I photographed it because I could not trust myself with that much cake around the house and it was a hit!! Just decorate it simply and ta-da, it comes together so easily. Top it with St. Patty’s sprinkles or get a little creative, but either way this is one of those desserts everyone will love — plant-based or not.
Why You’ll Love This Recipe
- Chocolate heaven: Deep, rich chocolate flavor in every bite that really satisfies.
- St. Patrick’s Day ready: A decadent and delicious way to use Guinness in a dessert.
- Egg-free: Plant-based and still bakes up with the perfect crumb and texture.
- Easy to make: Straightforward steps and simple ingredients you likely already have.
- Crowd pleaser: One of those desserts everyone goes back for, no matter the occasion.
Ingredient Highlight: Guinness
Guinness is a dark Irish stout made from roasted barley, which gives it that signature deep, slightly bitter flavor. In baking, it doesn’t make things taste like beer — instead, it enhances the chocolate, adding richness and depth while also helping create a darker color and more tender crumb. The slight bitterness from the stout balances the sweetness of the cake and frosting, so everything feels more layered and not overly sweet. It’s one of those ingredients that quietly does a lot of work in the background and makes everything taste more complex.
Madly Delicious Must-Know Tips & Questions
- Don’t rush the bake: Check a little early, but let it fully set so the crumb holds.
- Use Dutch-process cocoa: It gives a smoother, deeper chocolate flavor.
- Let it cool completely: Frosting too early will melt everything.
Can I taste the Guinness in the cake?
Not really — it adds depth more than a noticeable beer flavor.
Can I make this ahead of time?
Yes, and it actually gets even better the next day once everything settles.
Do I have to use espresso powder?
No, but it helps deepen the chocolate flavor without making it taste like coffee.
Let’s Dish: Did You Know?
Using stout in baking has been around for a long time, especially in Irish and British cooking. Dark beers like Guinness are often used in cakes and puddings because the roasted barley naturally pairs with chocolate, enhancing both flavor and color. It’s a simple way to add depth without adding extra ingredients, which is why it shows up in both traditional and modern desserts. In fact, Guinness chocolate cake has become a bit of a modern classic, especially around St. Patrick’s Day when people lean into baking with stout. It’s one of those small additions that completely transforms a cake without making it complicated.
Looking for a stress-free St. Patty’s Day Dessert? Then try my Guinness Chocolate Cake with Chocolate Frosting!
This one is easy to make, full of depth, and perfect for St. Patrick’s Day or anytime you want something a little extra. Give it a try and tag me on Instagram @madly__delicious with #MadlyDelicious to share your take!
More Guinness Recipes
Guinness Chocolate Cake with Chocolate Frosting
Equipment
- 8×8 inch square pan
- Electric hand mixer,
Ingredients
- 1¼ cups all-purpose flour
- 5 tbsp Dutch-process cocoa powder
- ¾ cup granulated sugar
- ¾ tsp baking powder
- ¾ tsp baking soda
- ¾ tsp salt
- ¾ cup + 2 tbsp Guinness (or another dark beer)
- ½ cup + 2 tbsp unsweetened plant-based milk
- 5 tbsp neutral oil (avocado, sunflower or vegetable oil)
- 1 tsp apple cider vinegar
- 1½ tsp vanilla extract
Chocolate Frosting
- ½ cup plant-based butter, softened
- ½ cup Dutch-process cocoa powder
- 1¾–2 cups powdered sugar
- 2 tbsp unsweetened plant-based milk, divided
- 1 tsp vanilla extract
- Pinch of salt
- ¼-½ tsp espresso powder (optional; start with ¼ tsp and adjust)
Optional Toppings
- St. Patrick's Day sprinkles (green, gold, white, and shamrock mix)
- Chocolate curls
Instructions
- Preheat and Prep: Preheat oven to 350°F (175°C). Lightly grease or line an 8×8-inch pan.
- Mix the Dry Ingredients: In a medium bowl, whisk together 1¼ cups all-purpose flour, 5 tbsp Dutch-process cocoa powder, ¾ cup granulated sugar, ¾ tsp baking powder, ¾ tsp baking soda and ¾ tsp salt.
- Mix the Wet Ingredients: In a larger bowl, whisk together ¾ cup + 2 tbsp Guinness, ½ cup + 2 tbsp plant-based milk, 5 tbsp neutral oil, 1 tsp apple cider vinegar and 1½ tsp vanilla extract.
- Combine: Pour the dry ingredients into the wet ingredients and gently mix until just combined. Do not overmix.
- Bake: Pour the batter into the prepared pan and smooth the top. Bake for 28–34 minutes, or until a toothpick inserted into the center comes out clean or with a few moist crumbs.
- Cool: Let the cake cool in the pan for 10 minutes, then remove and transfer to a wire rack to cool completely before frosting.Tip: If you need to speed things up, place the cake in the refrigerator to chill more quickly.
- Make the Frosting: In a bowl, beat ½ cup plant-based butter with electric hand mixer until smooth. Add ½ cup cocoa powder and mix until combined — it will look dry and crumbly, and that’s normal. Gradually add 1¾–2 cups powdered sugar, then mix in 1 tbsp plant-based milk, 1 tsp vanilla extract, a pinch of salt, and ¼–½ tsp espresso powder (if using). Beat until smooth adding splashes of the other tbsp of milk as needed. Beat until smooth, adding splashes of the remaining 1 tbsp plant-based milk as needed, until creamy.
- Frost and Serve: Spread the frosting evenly over the cooled cake, then use the back of a spoon to create soft swoops and texture. Top with St. Patrick’s Day sprinkles, slice, and serve.