My grandparents were a great team when it came to preserves. Granddad was a skilled and very prolific gardener and Nana could turn anything that wasn’t used fresh into wonderful jams, pickles, chutneys and sauces. This is their recipe for pickled onions, which were made and stored for a couple of months to be brought out at Christmas time.
I like it because you don’t need to boil the vinegar and that always makes the whole house smell for days afterwards! Using cold vinegar also keeps the onions nice and crunchy, as does soaking overnight in a weak sugar or salt solution. Using sugar has the added advantage that it brings out the natural sweetness of the onions.
Any jars can be used but bigger is better, and a wide top makes it much easier to arrange the onions. Because the vinegar preserves the onions, sterilisation is not an issue, however, it is necessary to protect metal screw top lids by putting a large circle of waxed paper or plastic wrap between the top of the jar and the lid, as any scratches in the coating on the lid with allow the metal to rust. Plastic lids or ‘Kilner’ style jars with a rubber seal and glass lid will be fine without. If the lids are missing buy ‘jam covers’ complete with greaseproof paper disks and elastic bands, they’re not ideal for long storage but they’ll do the trick short term.