In a heatproof bowl, melt the dark chocolate over boiling water. Once melted, pour onto a baking tray lined with baking paper and spread to form a large rectangle, at about 2mm thick. Place in the fridge while you melt the white chocolate. I cleaned and dried the bowl I used for the dark chocolate and then melted the white. I also chopped the candy canes finely while the chocolate was melting.

Once the white chocolate has melted, get the other chocolate out of the fridge, and spoon the white chocolate on top until it is covered. With the back of the spoon make little swirly motions - as the white chocolate melts the dark chocolate underneath it, it will start to come through and look like a marbled effect.

Once you've done this, then sprinkle the crushed candy canes on top, and set in the refrigerator for at least 30 minutes until set. Keep refrigerated until ready to eat.