In a small bowl, combine potatoes, 2 tablespoons oil, rosemary and garlic; toss to coat. Place mixture in a rimmed, large baking sheet. Roast at 400 degrees for 25 minutes, stirring once.
Drizzle asparagus with remaining oil; add to pan. Bake 15 to 25 minutes longer or until vegetables are tender, stirring occasionally. Sprinkle with salt and pepper. Garnish with shaved Parmesan, optional.