Steaks with Sauce Bordelaise

Ingredients

• 2 ounces beef bone marrow 2-inch-thick (from four beef crosscut shank bones)
• 1 cup wine dry red
• 4 servings parsley fresh chopped
• 1 cup beef broth 
• 1 large shallots finely chopped
• 4.5 inch fat-trimmed beef flank steak (each 8 ounces)
• 6 tablespoons butter unsalted chilled ()

Equipment

• bowl
• frying pan
• sauce pan
• whisk
• slotted spoon

Directions

1. Bring broth to simmer in heavy small saucepan over medium-high heat.
2. Add marrow; reduce heat to low and poach gently until marrow looks translucent and gray, about 2 minutes. Using slotted spoon, transfer marrow to small plate. Refrigerate marrow poaching liquid. Refrigerate marrow until cold and firm, about 45 minutes. Dice marrow finely; cover and chill. (Can be made 1 day ahead. Keep marrow and poaching liquid chilled.)
3. Melt 1 tablespoon butter in heavy medium skillet over medium-high heat.
4. Add shallot and sauté until translucent, about 3 minutes.
5. Add wine and boil until reduced to scant 1/2 cup, about 5 minutes.
6. Transfer reduction to small bowl.
7. Melt 2 tablespoons butter in heavy large skillet over high heat.
8. Sprinkle steaks lightly with salt and pepper.
9. Add to skillet and sear until cooked to desired doneness, about 3 minutes per side for medium-rare.
10. Transfer steaks to plates.
11. Add wine reduction to skillet and bring to boil, scraping up browned bits. Reduce heat to medium.
12. Whisk in remaining 3 tablespoons butter, 1 tablespoon at a time.
13. Add 1/4 cup reserved marrow poaching liquid and diced marrow. Cook until marrow melts and sauce is smooth, whisking constantly, about 2 minutes. Thin sauce with more poaching liquid by tablespoonfuls, if desired. Season sauce with salt and pepper. Spoon sauce over steaks.
14. Sprinkle with parsley.