Thinly slice potatoes. Place into a non-reactive (i.e. glass) bowl. Combine with onions. Prepare the basic vinaigrette. Combine with potatoes and onions while still warm (this way the flavor soaks in). Allow to sit and absorb more flavor for a couple of hours or even overnight.
Tomatoes, thinly sliced, may also be added to this recipe, for additional flavor and color. This recipe is terrific for outdoor bbqs and parties as vinegar does not go bad, unlike mayo.
This recipe was created by a contestant during a cooking competition. It has not been tested for home use.
Recipe courtesy of Daria Doubek-Thompson for FoodTV.com's Potato Salad Championship Cook-Off Competition, 2001