answer:You can add vanilla extract or “vanilla syrup” to a coke. In olden days, one could get a coke at the soda fountain. The syrup came out of a pump, then carbonated water was added and ofter a flavor, such as cherry or chocolate. It is easy to make versions of these in your kitchen, using coke over ice as a foundation. Sorry: Here’s the link for a high-quality vanilla syrup. If you use vanilla extract, make sure it is pure vanilla and not fake stuff.