PREHEAT oven to 350°F. Mix potatoes, onions and ham; spoon into greased 9-inch pie plate. Sprinkle with cheese.
BEAT eggs and milk in small bowl with wire whisk until well blended. Add dressing, salt and pepper; mix well. Pour evenly over potato mixture.
BAKE 25 to 30 min. or until centre is set. Let stand 10 min. Cut into wedges to serve.
