Choc Mint Cake Bars
A chocolate cake topped with peppermint icing and dark chocolate.

I’ve been baking up a storm recently for friends and family. My kitchen was over-run with 60 decorated unicorn cookies prepared for my Niece’s First Birthday. They were such a blast to make, and the recipe, decorating instructions and video are coming soon.
Then I tackled a two-tiered pink and gold bridal shower cake. I think I developed a few extra grey hairs in the process! I’m definitely more of a baker than a decorator.
So when looking for baking inspiration for The Cake Mistress I wanted something simple. In an old 1970s cookbook, I spotted a recipe for “Peppermint Slice”. Browsing the recipe, I realised it would turn out more like a soft iced sheet cake than a firmer “slice” as we know them. Which is okay by me. As long as it’s sweet and edible, I’m on board.
My adapted Choc Mint Cake Bar recipe is easy to make. First, you bake a regular chocolate cake in a sheet pan, slice tin or “Lamington” tin (for the Aussies), and top it with a shiny mint glace icing. Once that’s set, you pour a layer of melted chocolate on top and leave it to set. Et voila! A delicious chocolate mint cake to serve.
HOW TO MAKE CHOC MINT CAKE BARS
Click to watch how to make Choc Mint Cake Bars
CHOC MINT CAKE BARS
Makes: 16 at least Difficulty: Easy
EQUIPMENT:
20 x 30 cm deep baking tray
INGREDIENTS:
Chocolate Cake
165g Self Raising Flour
180g Caster Sugar
½ teaspoon Bicarbonate Soda
40g Cocoa Powder
70g Unsalted Butter, softened to room temperature
125ml Water
½ teaspoon Vanilla Extract
2 Eggs, lightly beaten
Peppermint Icing
1 teaspoon Vegetable Oil
300g Icing Sugar
¼ teaspoon Peppermint Essence
Green food colouring
3-4 tablespoons Milk
Chocolate Topping
200g Dark Chocolate, finely chopped
METHOD:
Preheat the oven to 180 degrees Celsius (160 fan-forced; 350F). Line the base of the baking tray with baking paper and grease the sides with non-stick spray.
Add the flour, sugar, butter, bicarbonate soda, cocoa powder, water and vanilla to a large mixing bowl. Use a hand-mixer to cream the batter together until thick and creamy. Add the eggs and whisk with the mixer for two minutes.
Scrape the batter into the prepared cake tin. Place on the middle rack of the oven and bake for 25-30 minutes. The cake is ready when the top springs back when lightly touched and a skewer into the middle comes out clean.
Remove cake from the oven and allow it to cool completely.
When the cake is cool, prepare the peppermint icing. Add the oil, icing sugar, peppermint essence, 3 drops of green food colouring and milk to a bowl. Stir together vigorously over a bowl of hot water until glossy.
Pour the mint icing evenly over the cake. Quickly spread the icing to the edges but don’t move it around too much or it becomes grainy. Let the icing set.
When the icing has set, melt the chocolate and spread it evenly over the top of the mint icing. Allow the chocolate to set hard.
To serve, cut the cake into bars. Use a hot knife to help cut cleanly through the chocolate.
BAKING TIPS:
- Make sure the peppermint icing has set completely before adding warm melted chocolate on top
- To cut the bars cleanly, use the “hot knife” method. Fill a bowl with hot water. Leave your cutting knife in the hot water for 10 seconds, wipe the blade dry, then cut through the set chocolate layer. As the knife cools re-soak it in hot water.

Prep Time | 2 hrs |
Cook Time | 30 mins |
Passive Time | 1 hr |
Servings |
cake bars at least
|
- 165 g Self Raising Flour
- 180 g Caster Sugar
- 1/2 teaspoon Bicarbonate Soda
- 40 g Cocoa Powder
- 70 g Unsalted Butter softened to room temperature
- 125 ml Water
- 1/2 teaspoon Vanilla Extract
- 2 Eggs lightly beaten
- 1 teaspoon Vegetable Oil
- 300 g Icing Sugar
- 1/4 teaspoon Peppermint Essence
- 3-4 tablespoons Milk
- Green food colouring
- 200 g Dark Chocolate finely chopped
Ingredients
Chocolate Cake
Peppermint Icing
Chocolate Topping
|
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- Preheat the oven to 180 degrees Celsius (160 fan-forced; 350F). Line the base of the baking tray with baking paper and grease the sides with non-stick spray.
- Add the flour, sugar, butter, bicarbonate soda, cocoa powder, water and vanilla to a large mixing bowl. Use a hand-mixer to cream the batter together until thick and creamy. Add the eggs and whisk with the mixer for two minutes.
- Scrape the batter into the prepared cake tin. Place on the middle rack of the oven and bake for 25-30 minutes. The cake is ready when the top springs back when lightly touched and a skewer into the middle comes out clean.
- Remove cake from the oven and allow it to cool completely.
- When the cake is cool, prepare the peppermint icing. Add the oil, icing sugar, peppermint essence, 3 drops of green food colouring and milk to a bowl. Stir together vigorously over a bowl of hot water until glossy.
- Pour the mint icing evenly over the cake. Quickly spread the icing to the edges but don’t move it around too much or it becomes grainy. Let the icing set.
- When the icing has set, melt the chocolate and spread it evenly over the top of the mint icing. Allow the chocolate to set hard.
- To serve, cut the cake into bars. Use a hot knife to help cut cleanly through the chocolate.
- Make sure the peppermint icing has set completely before adding warm melted chocolate on top
- To cut the bars cleanly, use the "hot knife" method. Fill a bowl with hot water. Leave your cutting knife in the hot water for 10 seconds, wipe the blade dry, then cut through the set chocolate layer. As the knife cools re-soak it in hot water.
You might like to explore our other cake recipes, like Chocolate Fudge Cake, Mocha Fudge Cake Bars, and Easy Chocolate Cake. Chocoholics, we have a whole section on baking recipes with chocolate too.
These look so rich and delicious!
I have to make this for my daughter — she is a chocolate mint FIEND!
You had me at mint and chocolate. That’s my favorite combination ever! I can’t wait to try these, thanks!
I love the hint of green right underneath the chocolate layer. It’ll make for such a pretty Christmas presentation.
I love chocolate and mint together. It’s one of my favorite flavor combinations! I can not wait to chomp into one of these glorious bars!
wow!!! looks so delicious Emma. Great combination of flavours
Hi there Emma,
I’ve made a couple of your cakes so far and they’ve become faves at home and outside so thank you!!
With this cake, I wanted to make it today because it looks delish but seems you’ve left out the butter. It’s in your video but not your ingredients. Can you please advise how much butter?
Thanks!
Oh no! I totally forgot the butter in both the ingredients and the method. Thanks for spotting it. You’ll need 70g (2.5 oz) of Unsalted Butter, softened to room temperature to help you beat it into the other ingredients. Hope it turns out really well for you. Thanks for trying the other recipes too! Happy baking x Emma.
Awesome! Thanks so much!! I’ll definitely bake this up next weekend:)
(Ps I had already baked it yesterday without butter, and my boys still ate it, I can only imagine what they’ll do to it when it has the butter in it!!! Might have to do 2 batches :) )