To your crockpot, mix heavy cream and unsweetened cocoa powder together. It takes a few minutes for it to come together so it’s best to do this first.
Add milk, sweetened condensed milk, chopped chocolate and vanilla extract. Stir.
Set crockpot to low for 2-3 hours and stir approximately every 45 minutes to prevent any burning.
Enjoy with whipped cream, marshmallows or any other toppings that you like!