Pour all the liquid ingredients into a slow cooker and wisk to combine. Add chocolate chips and turn slow cooker to high. Allow the hot chocolate to heat on high for 2 hours stirring occasionally until all the chocolate has melted and is heated through.
Once the chocolate has melted and the milk is warmed through, turn the heat down to low. Do not allow to boil.
Serve on its own or with whipped cream and mix ins of your choice.