1medium-large red onionsliced as thinly as possible*
1/4 to 1/2teaspoonred pepper flakes(optional)
1/4cup+ 1 tablespoon distilled white vinegar
1/2cup+ 2 tablespoons150 mL water
1tablespoonorganic cane sugaror maple syrup
2teaspoonskosher salt
Instructions
Use warm soapy water to wash a 1-pint jar, lid and sealing ring. Rinse well. Add the onions and chili flakes (if using to the jar), packing the onion jar as tightly as you can without smushing it. Make sure there is ½ to 1-inch of space from the rim of the jar to the tops of the onions.
Bring the vinegar, water, salt, and sugar to a boil in a small saucepan, whisking to dissolve the sugar and salt. Over the sink, pour the hot brine over the onions and submerge, pressing down on them with the end of a wooden spoon if needed.
Gently tap the jar against the counter a few times to remove all the air bubbles. Top off with more brine if necessary, and seal the jar(s).
Let the jar cool to room temperature before refrigerating. Taste the pickled vegetables after 8 hours, but try to wait for 48 hours to allow the flavors to more fully develop.Store in the fridge for 2 to 3 weeks.