Bitter radicchio, balanced by salt, prosciutto, and walnut oil, finds a place in this well-rounded salad that features all five major tastes. Substitute extra-virgin olive oil for walnut oil, if you prefer.
Cook haricots verts in boiling water 2 minutes or until crisp-tender. Drain and rinse with cold water; drain.
Combine oil, balsamic vinegar, honey, salt, orange rind, and Dijon mustard in a large bowl; stir well with a whisk. Add haricots verts, lettuce, and remaining ingredients to bowl; toss gently to coat.