Spices! And/or herbs. Your options are wide open: mini jars, a custom spice blend, paper packets, a single herb, custom printed labels, a simple ribbon, etc. Spice wedding favors are probably a safer bet than other types of edible wedding favors – which are by far your favorite kind of favors if the polls I’ve posted are any indication – if only because more of your guests may find a use for an unfamiliar spice than would like something like truffles or maple syrup.
And if you love the idea but want to take it up a notch, you can always pair your spice wedding favors with a mini ceramic mortar and pestle, squee!