This recipe is for refrigerator pickles. It is not suitable for canning or storing the pickles at room temperature
Remove the peel from the red onion and slice it into thin slices, about 1/8 inch thick. Fill your half pint jar with red onion slices as you go so you know when you have sliced enough onion.
1 large or 2 small red onions
In a small saucepan combine the cider vinegar with water. Then add the salt, sugar, peppercorns and cumin.
1/2 cup cider vinegar, 1/2 cup water, 3/4 teaspoon salt, 1 Tablespoon sugar, 1 teaspoon peppercorns, 1 teaspoon cumin
Heat over medium heat until the salt and sugar dissolve, then take the pan off the heat.
Pour the hot brine over the onions in the jar, filling to about 1/4 of an inch from the top.
Put a lid on the jar and let it sit at room temperature for half an hour.
The pickled onions are ready to use after 30 minutes. They will become sweeter and pinker over time. Put them in the refrigerator where they will keep for 2-3 weeks.
Notes
Sometimes the spices don't go in the jar when you pour the brine. If this happens just use a spoon to transfer the spices to the jar.
If the amount of brine you made doesn't quite cover the onions you can top the jar off with hot water.