Step 1Clean the potatoes under running water, removing any spots. Cut any large potatoes in half. Steam the potatoes until tender, 25 to 30 minutes. Place the potatoes in a serving bowl.
Step 2Combine the truffle oil, olive oil, white wine vinegar, shallot, chives, salt and pepper to taste in a mixing bowl. Stir in the minced prosciutto.
Step 3Pour the vinaigrette over the hot potatoes and stir to coat. Let the potatoes marinate about 15 minutes.
Step 4Just before serving, stir in the romaine leaves. Divide the warm salad among 4 serving dishes and sprinkle with the chopped egg. Drape 2 thin slices of prosciutto over the top of each salad.