Peel and thinly slice the red onion and peel and smash the garlic clove. Put all ingredients in pan and bring to a boil.
Once boiling remove the pan from the heat, cover and let come to room temperature.
You can use the pickled onions immediately.
If you have time let them sit in the refrigerator overnight to soften the onions.
To store the pickled onions keep submerged in liquid in a non reactive container like glass or plastic, NOT aluminum.
The pickled onions will last a couple of months. If you see any mold or sludge toss. But in such an acidic environment they should be fine in the refrigerator for up to 8 weeks.
