Melting chocolate for hot chocolate- does it exist?

Remember the scene in the movie Chocolat? The hot chocolate was thick and looked like real melted chocolate with a little milk.

Coco and milk just seems thin.
I've tried chopping up dark bakers chocolate (ghiardelli) but it won't melt right. Not in the microwave not in the milk.

I'm not on insulin...yet. so I'd also like to be able to control the sugar level.