1/4 cup Worcestershire sauce
1/4 cup extra-virgin olive oil, plus for rolls
1 tablespoon hot sauce
6 cloves garlic
1 flank steak (about 3 pounds)
6 hero sandwich rolls
2 tablespoons extra-virgin olive oil
3 medium red onions, sliced 1/3-inch thick
3 cloves garlic, smashed
1 1/2 teaspoons salt
1 teaspoon chopped fresh thyme leaves
1/2 teaspoon hot sauce
1/2 cup low sodium-canned chicken broth
4 ounces blue cheese, crumbled (about 1/2 cup)
1 cup mayonnaise or sour cream, or combination
1 lemon, zest finely grated
Mix the Worcestershire, olive oil, hot sauce, and 5 cloves of chopped garlic in a large glass baking dish. Add the steak, turning until evenly coated. Marinate at room temperature for 15 to 30 minutes, or cover and refrigerate for up to 4 hours, flipping the steak once or twice.
Heat a large skillet over medium-high heat, add the olive oil and when shimmering add the onions. Cook, stirring occasionally; until the onions are brown, then stir in the garlic, salt, thyme, and hot sauce, cook until onions are tender. Add the broth and scrape up any browned bits from the bottom of the pan. Cook until all the chicken broth is gone, and then season with pepper.
Remove the steak and season 1 side with salt and pepper. Place seasoned side of the meat down on the grill. Cook the steak undisturbed for 5 minutes. Season the other side of the steak with salt and pepper and flip. When done let the meat rest for 15 minutes.
Meanwhile, mash the blue cheese in a bowl with the mayonnaise or sour cream, lemon zest, and pepper, to taste.
Cut the rolls in half and brush the insides with olive oil. Grill until warm on each side, about 1 minute. Rub the toasted bread with the remaining clove of garlic.
Thinly slice the meat across the grain and assemble the sandwiches. Spread a few tablespoons of the blue cheese sauce on each sandwich, top with some of the steak and onions.