These are a simple garnish to any salad or meat dish, and I love the color. Thinly slice a red onion and stuff into a jar. Mix warm water, vinegar, salt and sugar in a bowl and pour over onion to cover. It can be served within a few hours and lasts for weeks in the refrigerator. I love serving this over pork dishes and on top of simple salads.
Pickled Onions from Bon Appetit:
½ cups apple cider vinegar
1 tablespoon sugar
1 ½ teaspoons kosher salt
1 red onion, thinly sliced