2.Simmer the Brine:Dissolving solutes for maximum extraction.
In a small saucepan, combine the apple cider vinegar, white vinegar, water, kosher salt, and cane sugar. Place over medium heat and bring to a gentle simmer, stirring just until the salt and sugar are completely dissolved. Do not let it boil away vigorously.
3.Pour and Infuse:Thermal extraction creates the magic juice.
Carefully pour the hot pickling liquid over the red onions in the jar, ensuring all the aromatics and onion slices are completely submerged. Press down with a spoon if necessary.
4.Cool and Steep:Developing complexity at room temperature.
Allow the jar to sit uncovered at room temperature for about 30 to 45 minutes until it reaches room temperature. As it cools, the liquid will extract the water-soluble pigments (anthocyanins) from the onions, transforming into a striking magenta juice.
5.Strain or Store:Ready for culinary deployment.
Seal the jar tightly. You can keep the onions and juice together, or strain out the liquid to reserve pure pickled onion juice in a dedicated squeeze bottle for seasoning marinades, dressings, and cocktails.
