How to make
Heat the olive oil in a suitable pan.
Cut the red onion into thin slices. Put them in the bowl with the fat and add the sugar.
Leave the onion to stew. When the onion has completely softened, add the red wine and leave the alcohol to evaporate and the mixture to reduce. Add balsamic vinegar and stir.
Leave the jam to cook for a few more minutes and remove the pan from the heat.
Serve the red onion jam as a side dish or close it in a jar.
