Onions never looked (or tasted) so good! Try these atop a burger or in a salad. You can also use the brine as a vinaigrette.
Combine all ingredients except onions in a stainless steel pot and bring to boil. Stir in onions, remove from heat and let cool to room temperature. Once cooled, place in a glass or plastic container and refrigerate for 3 days to fully pickle. Use pickled onions on your favorite burger or mix into a green salad. For best results, use within about 2 weeks.