Lay the prosciutto slices on a cutting board and cut in half lengthwise. It's easier to wrap the asparagus with half of a slice. Wrap one slice of prosciutto around each asparagus spear, starting at the bottom, and spiraling up to the tip. Place the wrapped spears on the rimmed baking sheet. Sprinkle the asparagus with the lemon zest and parmesan cheese. Roast for another 3-5 minutes. Remove from the oven and serve warm.