Step 1

Peel and cut the onion into very thin slices. Use a mandolin to achieve super-thin shaved onion slices.

Step 2

Separate the cut onion into individual slices, and then pack them into a glass container.

Step 3

Combine the vinegars, water, salt, sweetener of choice, and any other optional seasonings in a saucepan. Heat over a medium-high heat until it begins to simmer and the salt/sugar dissolves. Remove from heat.

Step 4

While the brine is still warm (but not piping hot), pour it over the onions until the container is completely full.

Step 5

Let the pickled red onions sit out at room temperature for 30 to 60 minutes to marinate. You can enjoy them immediately thereafter, or move to the refrigerator where they’ll continue to develop flavor.

Step 6

Store in the refrigerator, and use within 2 weeks for the best quality and texture.