Pickled Red Onions

• ½ cup (120 ml) red wine vinegar
• 1 teaspoon kosher salt

Combine the vinegar and salt in a saucepan and bring to a simmer. Put the onions in a glass jar and pour the vinegar over them. Cover and refrigerate for at least 1 day before using. The pickled onions will hold for several weeks in the refrigerator.