Grease and line with baking paper a 25cm x 16cm x 2 ½cm (10in x 6in x 1in) baking tray. Make sure the paper has a 2cm over hang.
Melt Copha in microwave on high or in saucepan until fully melted. Using a food processor, crush biscuits until they resemble fine breadcrumbs.
Mix melted Copha and biscuit crumbs together. Then press biscuit mix into baking tray firmly, using the back of a spoon if necessary. Put in the fridge to set for 10 to 15 minutes.
White chocolate crackle layer
In a large bowl, combine white chocolate and Copha. Place bowl over a pot of lightly simmering water. Stir occasionally until melted. Remove from heat.
Add icing sugar, Rice Bubbles, milk powder and coconut to the bowl. Stir to combine.
Pour crackle mix over the biscuit base and spread evenly. Put back in the fridge to set.
Dark chocolate layer
In a large bowl combine dark chocolate and Copha. Place over a pot of lightly simmering water. Stir occasionally until melted. Remove from heat.
Add icing sugar, Rice Bubbles, milk powder and coconut to the bowl. Stir to combine. Pour dark chocolate crackle mix over white chocolate layer and biscuit base and spread evenly. Put back in the fridge to set.
Assembly
Once set, slice crackle cut into 16 to 20 squares.
Recipe Notes
Crackle slices can be stored in an airtight container in the fridge for up to 4 days.