Recipe:
-1 medium-sized red onion
-1/4 cup white vinegar
-3/4 cup hot water
-3 tablespoons white sugar
-1 1/2 teaspoons Kosher salt
-8 or 10 whole peppercorns
Cut the onion in half, then slice it thinly. Place it in a bowl and cover with boiling water. After one to two minutes, strain and set aside.
To make brine, thoroughly stir together hot water, white vinegar, sugar, salt, and peppercorns.
To make pickled onions, pack the sliced onions into a pint-sized mason jar. Pour brine over them until they are completely covered. Let the jar cool down on the counter and then refrigerate it. The onions will be ready to eat after 24 hours, but they will taste even better if you wait for 3-5 days.