- 1 cup apple cider vinegar
- 1 cup water
- 2 Tbsp sugar
- 2 tsp kosher salt
- 1 tsp whole black peppercorns
- 1 tsp yellow mustard seeds
- 1 large red onion, thinly sliced
- Combine vinegar, water, sugar, and salt in a medium bowl. Whisk until sugar and salt dissolve.
- Divide spices between 3, 8-oz jars. Fill each jar with one-third of the sliced onions. Pour vinegar mixture evenly over the onions. Cover and let sit at room temperature for at least 1 hour before serving. Refrigerate up to 1 week.
- Add pickled onions to tacos, sandwiches, salads; delicious as a topping on steaks and chops.