Mix together the first amount of chocolate and golden syrup. Melt together gently. Place the cornflakes in a large bowl and pour the melted chocolate/syrup over them. Mix to combine thoroughtly.
180 g dark chocolate, 50 g golden syrup, 120 g cornflakes
Spread the cornflakes in the base of a large loaf tin (lined). Press down well to form a solid base layer. Chill in fridge until set.
Gently heat the peanut butter in a bowl (I used the microwave, 1 minute at 600 W) and stir in the icing sugar. Pour it over the chilled chocolate cornflake mixture and spread evenly to form the second layer. Chill in fridge.
220 g smooth peanut butter, 25 g icing sugar
Melt the second lot of chocolate and pour over the chilled peanut butter/cornflake slice. Spread evenly. Chill in fridge until set. Cut into slices to serve.