School Days Chocolate Concrete
, Updated Mar 25, 2025
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Chocolate concrete cake will take you straight back to your school days! This four ingredient chocolate crunch recipe is SO EASY and tastes insanely good. Serve warm with pink custard or just grab a slice – so yummy 🙂
You will also LOVE my Chocolate School Cake!
Fancy taking a trip down memory lane? Chocolate concrete – also known as chocolate crunch – doesn’t sound super appetizing but this old school recipe is as easy as it is yummy!
The crunch from the sugar topping giving way to a chocolate hit from the cocoa – just pure joy through and through. I’d say this is tied with my School Cake in nostalgia stakes.
Here’s why this is a MUST BAKE
- Only FOUR ingredients you probably already have!
- Vegan if you use vegan butter (margarine)
- So quick – ready in under 30 minutes
- Perfect for baking with your kids
Chocolate Concrete or Chocolate Crunch?
Chocolate crunch and chocolate concrete are one and the same. Some people like this crunchy chocolate cake served with pink custard (made using Pearce Duff’s strawberry blancmange powder for authenticity).
The chocolate crunch hardens to chocolate concrete as it cools. If you slice it warm straight out of the oven the texture will be slightly softer. I prefer just to grab a cold slice as a sweet treat – great with a cup of coffee or tea!
Cake or biscuit?
Technically this is a type of shortbread biscuit. Since the recipe contains no eggs and no rising agents it stays pretty flat. It is also easily vegan – just use margarine instead of butter.
Some chocolate concrete recipes contain eggs and baking powder – this to me is more of a cake and softer in texture… not really concrete / crunchy.
Cocoa Powder or Chocolate Powder?
Unsweetened cocoa powder will give your crunch a deeper chocolatey flavor. But don’t go buying the best organic super-dark cocoa powder. I like using the more economical Cadbury’s Bournville Cocoa in this recipe.
You CAN use drinking chocolate powder in a pinch, but your concrete won’t look as dark and the chocolate taste won’t come through as strongly.
Chocolate Concrete Recipe Step by Step
Full measurements and instructions can be found on the printable recipe card at the bottom of the page. Please take a look at the steps and video before attempting this recipe!
- Heat the oven to 180°C (350°F) or 160°C (325°F) if you are using the fan setting. Line a square tin with baking paper and grease with butter or spray with cake release.
- Mix the flour, sugar and cocoa using a fork or wire whisk until lump free and uniform in color. You can also sift the dry ingredients into your bowl.
- Melt the butter (in a pan or use the microwave) and pour into the bowl. Stir using a fork then use your hands to rub the butter into the dry ingredients until you have a crumbly sandy texture.
- Tip the mixture into your prepared tin and spread out. Place your hand inside a sandwich bag and press down hard to flatten the mixture or use the back of a spoon. It needs to be packed down into an even layer.
- Bake for 20 minutes. Remove from the oven and mist the hot chocolate concrete cake with a little water (I used a spray bottle) and sprinkle with the sugar.
- Cool on a wire rack and grab a slice as a sweet treat or serve with warm pink custard for a trip down memory lane!
Recipe Notes
- I like to slice the crunch cake while it is still a little warm, before it hardens into “concrete”. I cut mine into triangle shapes but you can cut into squares or whatever you like.
- Store the chocolate concrete slices in an airtight container for a few days (it never lasts 10 minutes in our house).
Looking for more retro school day treats?
HAVE YOU MADE MY CHOCOLATE CONCRETE RECIPE? Please leave a rating, post a photo on my Facebook page, share it on Instagram, or save it to Pinterest with the tag #supergoldenbakes and make my day!
School Days Chocolate Concrete with Pink Custard
Video
Ingredients
For the Chocolate Concrete
- 240 g (2 cups) flour (plain/all purpose)
- 225 (1 cup+ 2 tbsp) granulated sugar
- 60 g (8 tbsp) unsweetened cocoa powder
- 115 g (½ cup) unsalted butter or margarine
Topping
- 2 tbsp granulated sugar
- 1 tbsp pink sanding sugar (optional – just looks pretty!)
Pink Custard
- 600 ml (2 ½ cups) whole milk
- 1 packet strawberry blancmange powder (Pearce Duff’s)
- 3 tbsp caster sugar (or to taste)
Instructions
Chocolate Concrete
- Preheat the oven to 180C (350F) or 160C (325F) if you are using the fan setting. Line a square tin with baking paper and grease with butter or spray with cake release.
- Add the flour, sugar and cocoa powder into a mixing bowl and use a fork to stir together. You can also sift the dry ingredients into your bowl. Make sure the mixture is a uniform brown color without any lumps.240 g (2 cups) flour , 225 (1 cup+ 2 tbsp) granulated sugar, 60 g (8 tbsp) unsweetened cocoa powder
- Melt the butter (in a pan or use the microwave) and pour into the bowl. Stir using a fork then use your hands to rub the butter into the dry ingredients until you have a crumbly, wet sand texture.115 g (½ cup) unsalted butter
- Tip the mixture into your prepared tin and spread out. Place your hand inside a sandwich bag and press down hard to flatten the mixture or use the back of a spoon. It needs to be packed down into an even layer.
- Bake for 20 minutes. Straight away mist the hot chocolate concrete cake with a little water (I use a spray bottle) and sprinkle with the sugar.2 tbsp granulated sugar, 1 tbsp pink sanding sugar
- I like to slice the crunch cake while it is still a little warm. I cut mine into triangle shapes but you can cut into squares or whatever you like. Cool on a wire rack and grab a slice as a sweet treat or serve with pink custard.
- Keep the chocolate crunch in an airtight container (a metal cake tin) for a few days – in my experience it magically disappears as soon as it is sliced!
Pink Custard just like School!
- Heat the milk until warm – don’t allow it to come to boiling point. Put the blackmange powder and sugar into a saucepan. Add a splash of warm milk and stir well to make a paste.600 ml (2 ½ cups) whole milk, 1 packet strawberry blancmange powder, 3 tbsp caster sugar
- Gradually add the rest of the milk, stirring well. Heat the pink custard mixture on the stove over the lowest heat setting, stirring constantly, until it starts to thicken.
- If your custard is still a little lumpy then pass it through a fine sieve. Serve immediately – if the custard starts to cool it will form a “skin”.
Nutrition
Nutritional information is always approximate, and will depend on quality of ingredients and serving sizes.
We love jt, made it for quite a few bake sales at school and any fundraising. Usually one of the first things to go. Making more just now for school bingo night.