1. Preheat oven to 425°. Cut fingerlings in half lengthwise, and place in a large bowl. Toss with 1 Tbsp. olive oil, 1/2 tsp. salt, and 1/2 tsp. pepper. Place potato halves, cut sides up, in a jelly-roll pan. Toss green beans with remaining 1/2 Tbsp. oil, 1/2 tsp. salt, and 1/4 tsp. pepper, and place in another jelly-roll pan.
2. Bake potatoes at 425° for 30 to 32 minutes or until tender and browned. Remove from oven, and let potatoes stand in pan.
3. Bake green beans at 425° for 12 minutes.
4. Arrange green beans around roasted potatoes on a serving platter. Drizzle with Creamy Tarragon Dressing.
*1 1/2 lb. small red potatoes, halved, may be substituted with a bake time of 35 minutes. 1 1/2 lb. russet potatoes, quartered, may be substituted with a bake time of 40 minutes.