In 2-quart saucepan over medium heat, cook potatoes,
covered, in 2 inches boiling water until tender, about 12 minutes; drain
and set aside. Meanwhile, in small bowl, cover tomatoes with boiling water; set
aside 10 minutes while you whisk together dressing ingredients. Thoroughly drain tomatoes and pat dry with paper towels. Add potatoes, tomatoes and cucumbers to bowl containing dressing;
toss to coat. Mound potato mixture on plate. Arrange onion, cheese and olives on top.