Peppered Flank Steak With Chive-Buttermilk Mashers

I found this on Webmd, I think. It is a great meat and potatoes kind of meal. Marinate the meat before you get started.

• Ready In: 42 mins
• Serves: 4

Ingredients

• 1⁄4 cup  balsamic vinegar
• 1 (1 lb)  flank steak, trimmed
• 4 1⁄2 cups  cubed yukon gold potatoes (about 1 1/2 lb)
• 1⁄2 cup low-fat buttermilk
• 1  tablespoon butter
• 1  tablespoon  chopped fresh chives
• 1  teaspoon salt, divided
• 3⁄4 teaspoon  seasoned pepper (such as Lawry's)
•  cooking spray

Directions

1. Combine vinegar and steak in a large zip-top plastic bag.
2. Seal bag, and marinate in refrigerator 30 minute.
3. While steak marinates, place potatoes in a medium saucepan and cover with water; bring to boil.
4. Reduce heat, and simmer 15 minutes or until tender; drain.
5. Return potatoes to pan.
6. Add buttermilk, butter, chives, and 3/4 tsp salt; beat with a mixer at medium speed until smooth. Keep warm.
7. Preheat broiler.
8. Remove steak from bag; discard marinade.
9. Sprinkle steak with 1/4 tsp salt and seasoned pepper.
10. Place steak on broiler pan coated with cooking spray; broil 6 minutes on each side or until desired degree of doneness.
11. Cut steak diagonally across the grain into thin slices.