1Cut stalks from fennel bulb; reserve about 2 tablespoons greens (discard stems or save for making broth). On cutting board, place bulb, top side up. With sharp knife or mandoline, cut bulb in half, then cut into thin slices.
2In large bowl, mix orange peel and juice, oil, vinegar and salt with whisk. Add sliced fennel; toss to coat. Let stand at least 20 minutes.
3Just before serving, add arugula, cheese and reserved fennel greens; toss lightly.