1 Preheat the oven to 500 degrees F. or preheat the grill.2 In a large bowl, toss the potatoes with 2 tablespoons of the olive oil and salt and pepper.3 Spread the potatoes out in one layer on a non-stick baking sheet (or one lined with a nonstick liner).4 Roast until browned on one side, about 9 minutes, then turn and roast until browned on the other side, about 5 minutes more.5 In a small bowl, whisk together the remaining 2 tablespoons olive oil, white wine vinegar, shallot and salt and pepper to taste.6 Reserve about 18 potato slices for garnish. Place the rest of the potatoes in a large bowl, top with the arugula, and drizzle with the vinaigrette.7 Toss well and serve, garnishing each plate with the reserved potato slices and shaved Parmesan.