Ingredients:

  • 1 medium red onion (approx. 8 oz), thinly sliced
  • 1 cup apple cider vinegar
  • 1 tbsp granulated sugar
  • 1 tsp kosher salt

Instructions:

  1. Cut the red onion into thin, uniform half-moons, approximately 1/8-inch thick, and place them directly into a glass mason jar.
  2. Combine the apple cider vinegar, granulated sugar, and 1 tsp kosher salt in a small saucepan over medium heat (or a microwave-safe bowl).
  3. Stir constantly until the liquid is steaming and the salt and sugar have completely dissolved, ensuring the brine does not reach a rolling boil.
  4. Pour the hot brine over the sliced onions in the jar and press them down with a spoon to ensure every slice is fully submerged.
  5. Seal the jar with a lid and let it sit at room temperature for 30 minutes before moving the jar to the refrigerator.