Make the dressing. Whisk the mustard, lemon juice, olive oil, salt, pepper and honey in the bottom of a large bowl until creamy.
Add the beans, parsley and parmesan to the bowl with dressing. Gently toss until well coated. If making ahead, cover and refrigerate up to 3 days.
Add arugula and gently toss until dressed. Divide the salad between four salad plates, and then tuck the ham into the salad. Serve.