STEP 1
In a saucepan over low heat, melt the butter, caster sugar, cocoa powder, and golden syrup. Stir frequently until the mixture becomes smooth and well-combined. In a large mixing bowl, combine the crushed cornflakes, flour, and desiccated coconut. Pour the melted butter mixture over the dry ingredients, stirring well to coat everything evenly.
STEP 2
Grease a baking tray or air fryer-safe pan. Press the mixture firmly into the tray or pan to form an even layer. Preheat your air fryer to 340°F (175°C) and cook the mixture for 20 minutes, or until the top is firm and golden.
STEP 3
While the base is cooking, melt the milk chocolate. You can do this by microwaving it in 30-second intervals or by placing it in a heatproof bowl over a pot of simmering water. Stir in the vegetable oil for a smooth and glossy finish (optional).
STEP 4
Once the base is done and has cooled slightly, pour the melted chocolate over it and spread it evenly. Let the chocolate set at room temperature or place the tray in the fridge to speed up the process. Once the chocolate has hardened, cut into squares or bars and enjoy!