3 red onions
60 ml vinegar (grape or apple vinegar)
Boiling water to fill the jar
2 teaspoons salt (not heaped)
1 teaspoon sugar
Optional a few mustard seeds and peppercorns
Cut the onions into rings. Add sugar, salt, peppercorns, mustard seeds, vinegar and enough boiling water to fill the jar, close the lid and turn the jar 2-3 times to mix the ingredients. After about 6 hours, the onions are ready to eat.
Store in the refrigerator.