Ingredients

4

tablespoons vegetable oil

2

large onions, thinly sliced (2 cups)

2

tablespoons balsamic vinegar

1

teaspoon salt

1

teaspoon freshly ground pepper

4

oz blue cheese, crumbled (1 cup)

1/3

cup mayonnaise or salad dressing

1

beef flank steak, 3/4 to 1 inch thick (1 lb)

4

demi French baguette rolls (5 to 6 inches), cut in half horizontally

Preparation

In 10-inch nonstick skillet, heat 2 tablespoons of the oil over medium heat. Add onions; cook, stirring occasionally, 10 to 12 minutes or until deep golden brown. Add vinegar, 1/2 teaspoon of the salt and 1/4 teaspoon of the pepper; cook 1 minute longer or until liquid has evaporated. Remove from heat; set aside.

In small bowl, mix cheese, mayonnaise and remaining 1/4 teaspoon pepper. Set aside.

Heat gas or charcoal grill. Sprinkle steak with remaining 1/2 teaspoon of the salt and remaining 1/2 teaspoon of the pepper. Place steak on grill over medium-high heat. Cover grill; cook for 8- 10 minutes turning once for medium rare or until of desired doneness. Transfer steak to cutting board; let rest 10 minutes.

Lightly brush cut sides of rolls with remaining 2 tablespoons of the oil. Place rolls, cut side down, on grill rack. Cook 1 to 2 minutes or until golden.

Thinly slice steak across grain on the diagonal. Divide steak among bottom halves of rolls; top each with one-fourth of the onions. Spread cut sides of baguette tops with cheese mixture; place on top of onions. Serve immediately.