When thinly sliced, as in this sophisticated first course, raw artichokes retain a slightly sweet nuttiness that is perfectly accented by lemon, parsley, and ham.
Whisk lemon juice, salt, and oil in a medium bowl; set aside. Prepare the artichoke hearts: Working with 1 artichoke at a time, snap off tough outer leaves until half-green-half-yellow leaves are exposed. Using a chef's knife, cut off dark-green top until just pale part remains. Using a paring knife, peel dark-green layer from base and stem; trim stem. Scrape out purple leaves and fuzzy choke using a spoon, and discard. Halve artichoke lengthwise. Rub artichoke with 1/2 lemon as you work. Using a mandoline, cut artichoke heart into paper-thin slices, and add to lemon-oil mixture; toss.
Season artichokes with pepper. Add parsley and cheese; toss. Divide salad and ham among 4 plates, and serve with flatbread or crackers.
To preserve this salad's bright flavors, make it just before serving. Serrano ham, a Spanish cured ham similar to prosciutto, can be found at specialty stores.