01 - In a medium saucepan over low heat, combine the heavy cream and butter. Warm gently until the butter melts and the cream is just starting to simmer. Do not boil.
02 - Add the chopped dark and milk chocolate to the warm cream. Stir constantly until completely melted and smooth, ensuring all chocolate pieces are fully incorporated.
03 - Remove from heat and stir in vanilla extract and a pinch of sea salt until well combined.
04 - Pour the chocolate mixture into a fondue pot or heatproof serving bowl. Light the fondue burner or use a tea light to keep the chocolate warm and fluid throughout serving.
05 - Arrange the marshmallows, fruits, and cake cubes on a serving platter for easy access during dipping.
06 - Using fondue forks or skewers, dip your favorite treats into the warm chocolate and enjoy immediately while the fondue maintains its smooth, melted consistency.