I use vodka with anise buds soaked in it alittle vanilla coconut rootbeer anise extract and wnatever coffie I have leftover. Spray on shred tobacco till its damp and put in a sweter box for a week. I dont do it for flavor but to make it mild.
I've used a little molasses on some burley to toast it and tried flavoring some small cigars in a jar with cool-aid powder. Other than that I've only tried flavorings I bought at the store made for flavoring tobacco. The flavoring is from a company called Tasty Puff, it comes in a few dozen flavors of which menthol is the only one I really use and only rarely. Bourbon might be good, used to be my favorite drink