1 When ready place the sausages on the cooking zone of the barbecue. 2  Close the lid and let the sausages cook for around 10 minutes. 3  Pop the lid and insert your thermometer into one of the sausages, you should be around halfway at 35-40°C, flip them over once and replace the lid.ollow these steps to cook sausages perfectly every time. 1  Get the barbecue temperature to 180°C with coals to one side and a drip tray on the other. 2  When ready place the sausages on the cooking zone of the barbecue. 3  Close the lid and let the sausages cook for around 10 minutes.