Add ½ a cup of milk to a small saucepan and warm through. Remove from heat and add the gelatine sachets to the warm milk. Whisk through to dissolve and set aside.
Add the remaining 1 cup of milk to a medium sized saucepan, together with the cream, sugar and vanilla essence. Keep stirring until the sugar has dissolved and remove from heat.
Add the gelatine mixture to the cream mixture and combine well.
Coat your jelly mould or bundt pan with non-stick spray, then pour the mixture into the mould. Place in the fridge overnight or at least 6 hours to allow to set.