First, place apple cider vinegar, white vinegar, salt, and sugar into a mason jar. Screw the cover on and shake the jar until the salt and sugar have dissolved.
Then, place the sliced onion into the jar. Be sure that all of the onion is covered in vinegar.
Place the lid back on the jar and give it one more shake.
Finally, place the jar in the refrigerator for at least 2 hours or overnight for the optimal quick pickled onion!
Tips & Notes
*Option to add more sugar if you like sweeter pickled onions.