Quick Pickled Onions

1/2 cup apple cider vinegar

1 tablespoon sugar

1 1/2 teaspoon sea salt

1 red onion, sliced thin

Whisk vinegar, sugar, and salt into a small bowl.  Place sliced onions into a mason jar.  Pour vinegar mixture over the onions.  Allow to sit at room temperature for 1 hour.  Refrigerate for up to 2 weeks.