Dilute powdered milk with water pour to a pot,and set on heat, add butter, then bring to boil. Add grated chocolate.and stir well.

Mix cocoa powder,sugar and corm flour,with a lil water,then add to the boiling milk.

It will thickened be stirring to avoid lumps,off the heat when you reach your desired thickness.

Garnish with some whipped cream, chocolate,and grated chocolate.