I suppose it's a little late in the season to be posting this - but at least I'll have it here if I ever need it again.
This makes about 5 quarts of dry mix - and it costs about $12 to make.
8 qt box pwd milk (9 cups)
1 lb box pwd sugar (4 cups)
1 lb box pwd chocolate milk - like Nesquick (5 cups) *this makes pretty sweet hot chocolate mix - if you don't want it to be so sweet just put 4 cups of of the chocolate milk mix and then 1 cup of coco powder
10 oz jar pwd creamer (3 cups)
Mix all together in a large bowl. Store in a 5 quart container with a tight lid. 3 heaping spoonfulls for an 8 oz mug of hot water. (Don't use milk because of the powdered milk)