Steak Sandwiches with Grilled Onions

Marinating the steak with a delicious blend of Asian flavors and grilling it takes this classic sandwich to a new level.

PREP: 15 minutes plus marinating

GRILL: 12 to 15 minutes

MAKES: 4 servings

¼ cup soy sauce

¼ cup balsamic vinegar

1 tablespoon brown sugar

1 tablespoon fresh thyme leaves

¼ teaspoon ground black pepper

1 beef flank steak (about 1¼ pounds)

1 (12-inch) metal skewer

1 medium red onion (about 8 ounces), cut into 4 thick slices

8 slices sourdough bread, toasted on grill, if you like

2 ripe medium tomatoes (6 to 8 ounces each), sliced

1 bunch (5 ounces) arugula, trimmed

1. In large zip-tight plastic bag, mix soy sauce, vinegar, brown sugar, thyme, and pepper. Add steak, turning to coat. Seal bag, pressing out excess air. Place bag on plate; let marinate 15 minutes at room temperature or 1 hour in the refrigerator, turning several times.

2. Prepare outdoor grill for covered direct grilling over medium heat.

3. Meanwhile, for easier handling, insert skewer horizontally through onion slices; set aside.

4. Remove steak from marinade; pour marinade into 1-quart saucepan. Heat marinade over high heat to boiling; boil 1 minute.

5. Place steak and onion slices on hot grill rack. Cover grill and cook steak and onions, brushing both with marinade occasionally and turning over once, until onions are browned and tender and meat is medium-rare, 12 to 15 minutes. Transfer steak to cutting board; let stand 10 minutes to allow juices to set for easier slicing. Separate onion into rings.

6. Thinly slice steak diagonally across grain. Arrange onion rings and steak on 4 slices of bread; spoon any meat juices from board over onion and steak. Top with tomatoes, arugula, and remaining 4 slices of bread.

EACH SERVING: About 210 calories, 9g protein, 38g carbohydrate, 3g total fat (1g saturated), 5mg cholesterol, 815mg sodium