Grilled Flank Steak with Sauteed Portabella and Cremini Mushrooms

• 3 1/2 pounds flank steak
• 4 large shallots
• 1/3 cup balsamic vinegar
• 1/4 cup sugar
• 1/4 cup soy sauce
• Accompaniment: portabella and cremini mushrooms

1. Pat steak dry and cut crosswise at a 45 angle into 4 equal pieces.
2. Season steaks with salt and pepper and transfer to a large resealable heavy-duty plastic bag.
3. Chop shallots and in a bowl stir together with vinegar, sugar, and soy sauce.
4. Pour marinade into bag.
5. Marinate steaks, covered and chilled, turning bag over at least once, at least 2 hours and up to 2 days.
6. Prepare grill.
7. Remove steaks from bag and discard marinade.
8. Grill steaks on a lightly oiled rack set 5 to 6 inches over glowing coals 7 to 9 minutes on each side for medium-rare.
9. (Alternatively, grill steaks in 2 batches in a hot lightly oiled well-seasoned ridged grill pan over moderately high heat.)
10. Transfer steaks as cooked to a cutting board and let stand 10 minutes.
11. Cut steak at a 45 angle across grain into thin slices.
12. Serve steak with sauteed mushrooms.

flank steak, shallots, balsamic vinegar, sugar, soy sauce, accompaniment

Taken from www.epicurious.com/recipes/food/views/grilled-flank-steak-with-sauteed-portabella-and-cremini-mushrooms-15158 (may not work)