Layer the ingredients in a large serving bowl in the order in which they are listed. (Note: a clear glass bowl works best for this salad.) Chill well until ready to serve, at least 2 hours and up to 4 hours. Make the salad dressing while the salad is chilling and refrigerate in a nonreactive container, or make the dressing up to 1 day in advance.
Just before serving, drizzle some of the dressing over the salad. Serve the remaining dressing on the side. (Alternatively, serve the dressing separately and allow guests to dress their own salads - this way the salad will not become limp or soggy if it has to sit for any length of time.)
Makes 12 side salads or 6 to 8 main course salads