This dressing is for a German style potato salad, but works well as a dressing for lettuces as well. The fennel takes it into a Mediterranean direction, so if you want a true German style dressing eliminate the fennel and go with some caraway instead, but go lightly with that. Caraway can easily take over a dish. This recipe makes more than enough dressing for the potato salad recipe, but better more than not enough. If you just want the dressing for a salad, halve the recipe. Toasting the fennel seeds in this recipe give them a sweeter, drier flavor. Untoasted, the seeds are stronger and have a more licorice-like flavor. Using half and half will add another layer to the flavors. You could also use this recipe for a slaw with cabbage, carrots, and fennel.