Add all ingredients to a medium saucepan over medium heat. Stir regularly, until caramels and butter have melted, and the mixture is smooth and evenly combined. (See Notes for microwave instructions.)
Serve slightly warm, with apple slices for dipping. Store in a covered container in the refrigerator for up to two weeks, rewarming portions as needed.
Notes
To use a microwave instead of the stovetop: place ingredients in a large microwave-safe bowl and heat gently, in 20-30 second intervals, stirring often to avoid scorching.
Nutrition information is automatically calculated by Spoonacular. I am not a nutritionist and cannot guarantee accuracy. If your health depends on nutrition information, please calculate again with your own favorite calculator.