title_body: Is there a method to make flavored coffee without syrups?
upvoted_answer: I believe there are several ways to make flavoured coffees without syrup or sweetener.
  
  For example, I make vanilla coffee by mixing fresh vanilla seeds with finely ground medium-roast coffee, and seal the mixture for some time (duration depends on the weather). The result is quite nice, with a slight touch of vanilla. This is not a product---just for personal use and still exploring. The difference with syrup or essence or flavouring is that the touch feels lighter and more natural.
  
  
  
  A basic mechanism here is to mix ground coffee with some spice, and let the mixture sleep for flavour to spread.
  
  Another mechanism is to put some spice directly in a container with roasted beans. This seems more appropriate for spices like cinnamon (no need to extract seeds like for vanilla).
  
  I have not tried to mix spices with green beans, as the roasting stage changes a lot of things, but that should be an interesting path.