To make slaw: Process all vegetables in a food processor fitted with the metal blade until chopped fine. Place in a large nonreactive bowl.
To make dressing: Combine all ingredients in a nonreactive saucepan and simmer 5 minutes. Pour over the chopped vegetables. Place a plate over the vegetables which fits inside the diameter of the bowl and weight the plate down with a can or heavy glass. Allow to stand at room temperature 2 hours and then refrigerate overnight before serving. Makes 8 to 10 side-dish servings.