01 - Combine milk and heavy cream in a medium saucepan over medium heat. Warm until steaming but not boiling, stirring occasionally to prevent scorching.
02 - Add chocolate chips, caramel sauce, and sugar to the warm milk mixture. Whisk continuously until chocolate and caramel are completely melted and the mixture is smooth and uniform.
03 - Stir in sea salt and vanilla extract until fully incorporated. Taste the mixture and adjust sweetness or saltiness according to personal preference.
04 - Pour the prepared hot chocolate into two serving mugs, distributing evenly between them.
05 - Top each mug with whipped cream, drizzle with additional caramel sauce, and finish with a pinch of flaky sea salt. Serve immediately while hot.