Method

1. Trim the asparagus, cutting the spears in half if very long, Cook in a tall saucepan of lightly salted, boiling water over medium heat for 5 minutes, or until tender.
2. Drain, then run under cold water and drain again. Set aside.
3. Separate the prosciutto ham slices, cut in half, and wrap around the asparagus spears.
4. Arrange the salad greens on a large serving platter and place the asparagus spears on top.
5. Sprinkle Parmesan shavings.
6. To make the dressing, pour the vinegars and juice into a screw-top jar and shake until blended.
7. Pour over the salad and serve.