Preheat oven to 400 degrees F.
Toss parsnip chunks with olive oil and salt and pepper and place on a baking sheet. Roast until nicely browned, turning as needed, about 20 minutes. Let cool. Then toss with watercress, apple and shallot.
Whisk together dressing ingredients and season, to taste, with salt and pepper.
Recipe courtesy of Dave Lieberman