If you grew up in Australia, there's a good chance this old fashioned peppermint slice was a regular in your lunchbox or sitting proudly on the kitchen bench. A classic no-fuss treat is all about that perfect trio - a buttery base, creamy peppermint filling and a smooth chocolate topping.
It's one of those nostalgic recipes that never goes out of style… right alongside favourites like classic chocolate caramel slice and raspberry coconut slice. Simple, reliable, and always a crowd-pleaser!
A traditional peppermint slice is a layered slice recipe made with a slightly crunchy biscuit-style base, a sweet and creamy peppermint centre, and a firm chocolate topping. It's an iconic Aussie bakery-style slice that's been loved for decades - and for good reason!
If you love classic slices like baked lemon slice or anzac slice, this one deserves a spot on your must-bake list too. It's also incredibly versatile - perfect for lunchboxes, bake sales, or a simple afternoon treat with a cuppa.
Love this recipe! Have made it many times and it never fails, easy and delicious. I adore the little pop of minty green too - very fun! Thank you.
- Michelle
Why You're Going To Love This Recipe
- Easy to make - uses basic baking ingredients, and straightforward steps - it's a great recipe for beginners.
- Perfectly balanced layers - a buttery base, a smooth peppermint filling that's not overly sweet, and a rich chocolate topping to finish it off perfectly.
- Bake Sale super seller - always a popular slice at fetes and bake sales as it looks irresistible and tastes delicious!
- CWA tick of approval - this classic peppermint slice recipe comes from a very old Country Womens Assocation cookbook - that proves it's good!
- Thermomix-friendly - quick and easy steps are included in the recipe card.
Jump to:
Old Fashioned Peppermint Slice Ingredients
Have a look in the pantry, you may find almost everything you need, and the tiny bottles of extract and food colouring last a long time - you only need the smallest amount!
Note: Scroll to the recipe card at the bottom for the ingredients quantities and full detailed method.
- Copha - A solid white vegetable shortening made from coconut oil, essential for that traditional peppermint filling as it sets firmer than regular coconut oil.
- Peppermint extract & green food colouring - both are quite strong, so start with a small amount and add more gradually if needed.
- Icing sugar (pure icing sugar) - Choose pure icing sugar as your filling won't set properly with soft icing mixture.
- Chocolate + oil - Choose a quality brand of chocolate melts. Adding a little oil keeps the chocolate topping smooth and prevents cracking when slicing.
Variations
- Gluten-Free Peppermint Slice - Swap self-raising flour for a gluten-free SR flour blend (with xanthan gum included).
- No Copha Version - Use coconut oil, but expect a softer filling, this slice would need to be kept refrigerated.
- Dark Chocolate Topping - For a less sweet version, use dark chocolate instead of milk - it goes so well with the peppermint flavour.
- No Colouring - Skip the green food colouring for a more natural look - the flavour stays exactly the same.
How To Make Old Fashioned Peppermint Slice
This old fashioned peppermint slice comes together in just a few simple steps, layering a buttery base, creamy mint filling, and smooth chocolate topping - a perfect classic treat.
Note: Scroll to the recipe card at the bottom for the ingredients quantities and full detailed method.
- Mix the base dry ingredients: Mix the flour, coconut and brown sugar together in a bowl.
- Add butter: Stir through melted butter and mix until crumbly.
- Press into tin and bake: Press mixture firmly into a lined slice tin and bake until lightly golden.
- Prepare peppermint filling: Melt the copha, then add the sifted icing sugar, milk and peppermint extract and mix until smooth and creamy. Add colouring if using (optional).
- Spread the mint layer: Spread the peppermint mixture over the slightly warm base (this helps it spread easily). Chill until completely firm (about 2 hours).
- Add chocolate topping: Melt the chocolate with a little oil until smooth. Pour over the peppermint layer and spread evenly.
- Chill before slicing: Chill until just set, then slice while the chocolate is firm but not solid to avoid cracking.
Recipe Tips
- Use pure icing sugar - soft icing mixture will not set as firmly as pure.
- Spread the filling easily by using a warm knife.
- Don't overdo the peppermint essence - it is very concentrated and can quickly become overpowering.
- Let the base cool slightly, but not completely, before adding the filling. This makes the peppermint layer spread easier.
- Slice once the chocolate has just set for neat, clean edges.
- Store in an airtight container at room temp for up to 5 days, although refrigerate in warm weather to keep layers firm.
- Freeze slices (wrapped well) for up to 3 months.
Old Fashioned Peppermint Slice FAQs
It usually means the mixture needs more icing sugar or more chilling time. Make sure you use pure icing sugar and Copha (instead of oil) to help it set firmly.
Yes, but the filling will be softer and may need to be stored in the fridge.
Copha is made with more than 99% coconut oil and less than 1% soy lecithin, so while they are similar, Copha will certainly give a better result by setting firmer.
Chocolate usually cracks when it's too hard or set too firmly. To prevent this, add a little coconut oil when melting the chocolate to keep it softer and easier to slice. It also helps to cut the slice when the chocolate is just set - not fully hardened - and use a warm knife to glide through the top cleanly.
Absolutely! It's perfect for making 1-2 days in advance or freezing for later.
Not at all - it's purely for looks. The flavour stays the same without it.
More Peppermint Inspired Recipes
And so there you have it... a good old fashioned peppermint slice that is sure to become an absolute family fave!
WANT EVEN MORE DELICIOUS RECIPES? Subscribe to my newsletter or follow along on Facebook or Instagram. And if you love baking, then please come and join my Facebook cooking club group or subscribe to my YouTube channel.
Old Fashioned Peppermint Slice
Ingredients
- 200 g (1 ½ cups) self raising flour
- 90 g (1 cup) coconut
- 100 g (½ cup) brown sugar
- 185 g butter melted
- 375 g (3 cups) icing sugar pure, not soft icing mixture
- 60 g Copha
- 3 tbs milk
- 2 teaspoon peppermint extract
- 1-2 drops green food colouring optional
- 200 g chocolate melts milk or dark
- 4 teaspoon vegetable oil or coconut oil
Instructions
Conventional Method
- Preheat oven to 170 degrees celsius (fan-forced).
- Line an 18cm x 28cm rectangular slice tin with baking paper and set aside.
- To make the base, sift the self raising flour into a bowl. Add the coconut and brown sugar and stir to combine.
- Add the melted butter and mix well until crumbly and completely combined.
- Press the mixture firmly into the base of the prepared tin and smooth with a spoon.
- Bake for 20 minutes or until lightly golden. Set aside to cool slightly.
- Meanwhile, melt the Copha in the microwave. Sift over the icing sugar and add the milk, peppermint extract and green food colouring. Mix until smooth. If the mixture is too thick, add an extra tablespoon of milk and mix through.
- Spread the peppermint mixture over the top of the slightly warm slice base, then place tin into the fridge until completely cold (approximately 2 hours).
- Melt the chocolate and vegetable oil (or coconut oil) in the microwave on 50% power for 3-4 minutes, stirring every 30 seconds with a dry metal spoon.
- Pour the chocolate topping over the peppermint layer and chill for 30 minutes or until set. Cut into squares when the chocolate has hardened but not completely set.
Thermomix Method
- Preheat oven to 170 degrees celsius (fan-forced).Line an 18cm x 28cm rectangular slice tin with baking paper and set aside.
- Melt the butter in the Thermomix bowl for 3 minutes, Speed 2, 100 degrees.
- Add the self raising flour, coconut and brown sugar and mix for 15 seconds, Reverse, Speed 4. Scrape down the sides of the bowl and repeat for a further 15 seconds or until completely combined (use the spatula to help mix).
- Press the mixture firmly into the base of the prepared tin and smooth with a spoon. Bake for 20 minutes or until lightly golden. Set aside to cool slightly.
- Meanwhile, place the icing sugar into the Thermomix bowl and sift by mixing for 8 seconds, Speed 8. Pour the icing sugar into a separate bowl and set aside.
- Melt the Copha in the Thermomix bowl for 4 minutes, 100 degrees, Speed 2. Add the sifted icing sugar, milk, peppermint extract and green food colouring. Mix for 10 seconds, Speed 4. Scrape down the sides of the bowl and repeat 2-3 times or until smooth. Note: If the mixture is too thick, add an extra tablespoon of milk.
- Spread the peppermint mixture over the top of the slightly warm slice base and place into the fridge to cool completely (approximately 2 hours).
- Place the chocolate melts into a clean Thermomix bowl. Grate for 10 seconds, Speed 8. Scrape down the sides of the bowl, add the vegetable oil (or coconut oil) and melt for 4 minutes, 80 degrees, Speed 2.
- Pour the chocolate topping over the peppermint layer and chill for 30 minutes or until set. Cut into squares when the chocolate has hardened but not completely set.
Notes
- Use pure icing sugar - soft icing mixture will not set as firmly as pure.
- Spread the filling easily by using a warm knife.
- Don't overdo the peppermint essence - it is very concentrated and can quickly become overpowering.
- Let the base cool slightly, but not completely, before adding the filling. This makes the peppermint layer spread easier.
- Slice once the chocolate has just set for neat, clean edges.
- Store in an airtight container at room temp for up to 5 days, although refrigerate in warm weather to keep layers firm.
- Freeze slices (wrapped well) for up to 3 months.
Meagan says
Works well, I had to play with middle layer for consistency. I also added Doterra peppermint oil instead of peppermint essence plus juice from blitzing spinach in food processor instead of green food dye. I think middle layer is too sweet and would use 2/3rds icing sugar next time and more copha possibly?
Joanne says
I’ve frozen it before and it’s ok but best eaten fresh. There’s only 2 of us so I need to get a longer life out of them and freezing keeps them fresher longer
Bobbie says
Will this mint
slice freeze?
Lucy says
Hi Bobbie, I wouldn't recommend freezing this slice. xx
Lucy M says
what is a subsitute for copha cannot get this in the UK?? Help I really want to make this recipe for my husbands birthday, Thankyou, Lucy
Lucy says
Hi Lucy, copha is a vegetable shortening which is a white, solid fat made from vegetable oils. In the UK, I believe it might be called Trex, Flora White or Cookeen. And in the US it's known as Crisco.
Erin says
Is this all mixing with wooden spoon or electric?
Lucy says
Hi Erin, no you can just use a regular spoon or whisk!