I don't recall this being mentioned on this thread, but after looking at some sites about making milk chocolate, the product lecithin is mentioned in almost all that I've found, along with vanilla or vanillin. Also most mention butter or cocoa butter (looks like if I'm gonna try this I need some butter flavoring).
Lecithin is an emulsifier which means it has oils (fats) in it. I wonder if this could be a key ingredient to use, however, with it being an oil based substance, I wonder if it would be water soluble? Common knowledge would dictate that it would not since water and oil don't mix, however, I wonder if there's a process to make it soluble in ejuice?
Here's a few links I've found on making milk chocolate and about lecithin:
Ingredients- The Story of Chocolate
How to Make Milk Chocolate at Home | eHow
http://en.wikipedia.org/wiki/Lecithin#Food_additive
Any thoughts on this?