01 - Combine milk, heavy cream, granulated sugar, cocoa powder, and salt in a medium saucepan. Whisk thoroughly to incorporate the cocoa powder and dissolve sugar granules.
02 - Place the saucepan over medium heat, stirring frequently to prevent scorching. Heat the mixture until hot and steaming, ensuring all sugar completely dissolves. Do not allow the mixture to reach a boil.
03 - Remove from heat and stir in vanilla extract. Pour the warm base into the Ninja Creami pint container. Allow to cool to room temperature, then cover securely with the lid.
04 - Place the container in the freezer and freeze for at least 8 hours or overnight until completely solid. The base must be thoroughly frozen for proper processing.
05 - Remove the frozen pint from the freezer and process in the Ninja Creami using the Ice Cream setting. The machine will break down the frozen base into a creamy consistency.
06 - Create a deep well in the center of the processed ice cream. Add the marshmallow fluff, caramel sauce, and chocolate fish or chopped chocolate pieces into the well.
07 - Reinsert the pint into the Ninja Creami and run the Mix-In setting to swirl the toppings throughout the ice cream. Serve immediately for soft-serve texture, or freeze for 1-2 hours for firmer scoops.