peel and finely slice the onions into rings.
put the sausages and onions into the pan and allow them to cook slowly, turning and stirring regularly. cooking them slowly over a low heat with allow the sausages to cook through without the skins bursting and will soften the onions gently.
when the sausages are cooked remove them from the pan – refer to useful tips and links! – and set aside.
if the onions are not quite soft allow more time for them to cook. when they are ready, turn up the heat and add the red wine. allow the wine to bubble and reduce until the onions are coated in a sticky 