1 bunch Swiss chard stems, chopped
1 cup distilled white vinegar
2 cups sugar*
1/2 onion, thinly sliced
3 tablespoons Siracha*
1/2 teaspoon celery seed
Make a mixture of vinegar and sugar, then stir in onions, Sriracha, and celery seeds. Put chopped stems into a canning jar, pour the liquid over the chopped stems, using 3 cups liquid for every 1 1/2 cups chopped stems. Seal jars and place in the refrigerator for a 2-3 days to let the flavors develop.
* Reduce sugar or Siracha to manage spice or sweeteness level