Add the coconut milk, cream, oil, golden syrup and sugar to a large saucepan and cook over a medium heat, stirring often, for 3-4 minutes until the mixture combines and comes to a simmer.
Transfer the mixture to a blender, cover very tightly and blend for 30 seconds. Pour into an airtight container, then stir in the vanilla extract and a pinch of salt.
Cover the mixture and chill in the refrigerator overnight or until very cold. Pour into a wide freezable container, then freeze for 45 minutes. Remove from the freezer and give a vigorous stir with a whisk, breaking up any frozen sections.
Place back in the freezer and check every 30 minutes, whisking well each time. After 1½-2 hours, it should be quite thick. Carefully fold in most of the Oreo pieces, scattering the remainder over the top. Cover and freeze until solid.