In a large heavy based saucepan, combine the golden syrup, butter, brown sugar and cream. Bring to boil, stirring constantly until it reaches soft ball stage (113°C – 116°C on a candy thermometer). Remove from heat and add the vanilla essence, stirring in quickly.
Pour into the pan and let it cool completely, then place it in the fridge for 2 hours (or overnight). Remove from fridge and cut caramel into small pieces.
Melt chocolate according to instructions on packet and roll caramel in chocolate, placing in a container lined with baking paper. Alternatively using chocolate moulds, fill each half way up, place a caramel piece in, and top up with chocolate. Refrigerate for 1 hour or until chocolate is solid.