Chop chocolate into small pieces and melt in a glass container in microwave for 10-20 second intervals until melted.
Add in hot cocoa mix and sugar to melted chocolate. Mix until blended.
Add in 1/2 C milk, stir until smooth. Allow to cool to room temperature
In blender, place remaining milk, cooled chocolate mixture and ice cubes
Blend on high speed until smooth and consistency of a frozen daiquiri
Pour into mugs and top with whipped cream and sprinkles.
Video
Notes
I use a high powered VitaMix and find you get the best texture with a high speed blender. You can use a regular blender but you will get a chunkier texture. If using a regular blender, use crushed ice if possible.Use your favorite brand of hot cocoa mix. I usually have Nestle on hand!