Peel your apples, and cut each apple into 3 equal segments, removing the stem and core. Place your peeled apple segments in a large container or bowl, and submerge them with hot water from your tap. (Tap water at its hottest setting, is typically between 50-60 degrees Celsius, which is what we're aiming for - if not, adjust the temperature as needed!). Let your apples sit in the water for at least 10 minutes, or until we are done the next step.
While your apples are soaking, make your caramel! Using a 9" round cast-iron pan (you can also use another pot/pan to make your caramel, then transfer it to a 9" round baking dish after). Cover the bottom of your pan with an even layer of your granulated sugar, then drizzle your 1 tbsp vinegar and 1 tbsp water to cover the sugar (add more water if needed to cover the sugar). Turn your stove top to medium heat, and allow the sugar to come to a boil, before reducing into a caramel. What you are looking for with your caramel, is for a light brown colour to appear. Once you see this (likely just in one section of your pan, VERY CAREFULLY tilt your pan in a circular motion to make sure the sugar caramelizes evenly - but DO NOT stir or whisk your caramel at any point, or else it will crystallize. Once your sugar is evenly caramelized everywhere (now a thick, syrupy consistency), stop the caramelization by stirring in your cold butter. At this point it is okay to stir, and you will continue stirring for 2-3 minutes, or until the caramel is thick and emulsified (see video for a visual). Remove your caramel from the
heat
.
