Hey... :) Currently I work at a Starbucks. It is a creme base, it is basically what you would use to make ice cream....

Its a mixture of milk, sugar, and vanilla flavoring.
You would have to play with it a bit to get the right mixture, and I will be trying this next week, but it should taste like less sweet melted ice cream.

The whipping cream is Heavy whipping cream, and vanilla syrup. :)