1. Place the potatoes in a large pot, cover with cold water, and bring to a boil. Add 1? tablespoons salt, reduce heat, and simmer until tender, 12-15 minutes. Drain, run under cold water to cool, and slice. 2. Meanwhile, in a small bowl, whisk together the oil, vinegar, mustard, ? teaspoon salt, and ? teaspoon pepper. Using a fork or your fingers, shred the chidken, discarding the skin and bones. 3. In individual bowls, combine the arugula, chicken, tarragon, and potatoes. Drizzle with the dressing and sprinkle with the parmesan.