Download ImageIngredients1 red onion, thinly sliced1/2 cup apple cider vinegar or white vinegar1/2 cup boiling water1 tbsp sugar (cane sugar works)1 tsp sea saltMethodPeel onion and slice very thinly using a mandolin or a knife. Place the red onions in a jar.In a bowl add the vinegar, water, sugar and salt. Mix until the sugar is dissolved. Once dissolved, pour over your sliced onions.Use a spoon to mix and make sure onions are fully covered. Place the lid on the jar, let sit for an hour and then store in the fridge. Source : www.instagram.com