Roasted Fingerlings and Green Beans with Creamy Tarragon Dressing

I made this tonight with Chrissy's Goat Cheese and Prosciutto stuffed chicken breasts (coming tomorrow). This is a great meal to cook for company, and the whole meal only took me an hour. NOTE: I don't know if I messed up my salt measuring or what, but the potatoes were pretty salty, so go easy on the salt. Actually this is probably just because I used 1 pound of potatoes instead of 1.5, but just FYI.

What you need:
1.5 pounds fingerling potatoes** (I got these in the frigerated section at Trader Joes. Mine came in a one pound bag, so thats all I cooked.)
1.5 tablespoons olive oil, divided
1 tsp salt, divided
3/4 tsp cracked pepper, divided
1/2 pound tiny green beans (haricots verts) (I got a bag of frozen ones and used them)
Creamy Tarragon Dressing

**1.5 pounds small red potatoes, halved, may be substituted with a bake time of 35 minutes. OR 1.5 pounds russet potatoes, quartered may be substituted with a bake time of 40 minutes.

What you need for Tarragon Dressing:
1/4 buttermilk
2 tablespoons fresh lemon juice
1 tsp sugar
1 tsp dijon style mustard
3/4 tsp salt
1/4 tsp coarsely ground pepper
1/2 cup olive oil
2 tbsp finely chopped green onion
1 tbsp chopped fresh tarragon

What you need to do:
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. Bake potatoes at 425 for 30-32 minutes or until tender and browned. Remove from oven and let potatoes stand in pan. Bake green beans at 425 for 12 minutes (I just put them in when the potatoes had 12 minutes left so they were done at the same time). Arrange green beans around roasted potatoes on a serving platter. Drizzle with Creamy Tarragon Dressing.

What you need to do for Dressing:
Whisk together first 6 ingredients in a small bowl until combined. Gradually whisk in oil in a slow, steady stream, whisking constantly until smooth. Whisk in green onion and tarragon. Pour over potatoes and green beans. Use immediately, or store in an airtight container in refrigerator for up to 2 days. Let chilled dressing stand 30 mintues before using. Leftover dressing can be used on a salad.