School Days Chocolate Concrete Dessert Recipe

Chocolate concrete will take you straight back to school days. This simple chocolate crunch uses just four ingredients, is quick to make and delivers a satisfyingly crunchy, chocolatey treat. Serve warm with pink custard for a nostalgic dessert or enjoy a cold slice with tea or coffee.

Also known as chocolate crunch, chocolate concrete is an old-school favourite that’s both easy and delicious. The topping crisps to a crunchy sugar shell while the cocoa gives a deep chocolate hit. It’s closely linked in nostalgia to classic school tray bakes.

Why you should bake this

• Just four ingredients you probably already have.
• Can be vegan if you use margarine instead of butter.
• Ready in under 30 minutes.
• Great activity to bake with children.

Chocolate concrete or chocolate crunch?

They are the same thing: a simple, flat chocolate bake that crisps as it cools. If you cut it warm it will be slightly softer; once cooled it hardens into the characteristic “concrete” texture.

Cake or biscuit?

Technically this is closer to a shortbread-style biscuit since the recipe uses no eggs or raising agents and stays flat. Swap butter for margarine to make it vegan. Variations that include eggs and baking powder yield a softer cake-like texture rather than the classic crunch.

Cocoa powder or chocolate powder?

Unsweetened cocoa powder gives a deeper chocolate flavour and a darker colour. You don’t need the most expensive cocoa — a standard cocoa like Cadbury’s Bournville works well here. Drinking chocolate can be used in a pinch, but it will be lighter in colour and milder in chocolate intensity.

Chocolate concrete recipe — step by step

Full measurements and timings are listed in the recipe card below. Read the steps through before you start.

1. Preheat the oven to 180°C (350°F) — use 160°C (325°F) for fan ovens. Line an 8-inch (20cm) square tin with baking paper and grease it.
2. Mix the plain flour, granulated sugar and unsweetened cocoa powder in a bowl until uniform and lump-free. Sifting the dry ingredients helps.
3. Melt the butter or margarine and pour it into the dry mix. Stir with a fork, then use your hands to rub the fat into the dry ingredients until the mixture resembles wet sand or crumbs.
4. Tip the mixture into the prepared tin and spread it evenly. Press the mixture down firmly into a compact, even layer — use the back of a spoon or press through a sandwich bag to avoid greasy hands.
5. Bake for 20 minutes. Immediately after removing from the oven, mist the hot surface lightly with water (a spray bottle works well) and sprinkle over granulated sugar and optional pink sanding sugar for decoration.
6. Slice while slightly warm if you prefer a softer texture, or allow to cool completely for a harder “concrete” finish. Serve plain or with warm pink custard for a retro school-dinner treat.

Recipe notes

• Slice while a little warm for easier cutting, or wait until cool if you prefer a firm bar. Triangles, squares or fingers all work.
• Store slices in an airtight container for a few days; they keep well but rarely last long!

School Days Chocolate Concrete with Pink Custard