I saw this on pinterest quite a while ago, and finally remembered to pick up some rosemary at the farmers market last week so I can give it a whirl. It is supposed to be the scent they use at the williams sonoma store. Not sure I know what that smell is like, but this smells pretty good. Its kind of subtle though.
Two big sprigs of rosemary, slices of lemon and 1-2 tspn vanilla. Fill half way with water and simmer on very low. Add more water when necessary.