This recipe is not an original. I learnt the basics from my Aunty and have since altered some ingredients and methods which I found by trial and and error and my good friend google. For instance I learnt from the internet that if you soak your onions in boiling water for about 30 seconds, then put them in the sink with cold water, peeling them is so much easier. I use a pressure cooker to sterilize my jars. You can add up to 1 tbspn of brown sugar to the vinegar mix to sweeten a little. Use any vinegar you prefer, this is a good recipe to experiment with. Omit the chilli flakes if you dont like them but the finished onions are not very hot and the chilli does give a nice subtle tang. One other tip. If you double up on the recipe, no need to use double the amount of salt. I use just a pinch or so more only when I prepare 2 kilos of onions.