This pickled red onion dish has been with me for years. You can vary the flavour by using malt vinegar. Make a bigger batch and keep it in the fridge.
Warm the sushi vinegar, brown sugar, green chilli and star anise in a saucepan over a medium heat to infuse and dissolve the sugar.
Add the sliced red onion to the hot vinegar. Allow to cool and store in a jar until needed.
These onions will keep for two weeks in the fridge.