- 1/4 cup olive oil, extra virgin
- 1 tablespoon Worcestershire sauce
- 1/2 teaspoon salt, kosher
- 1/4 teaspoon black pepper, freshly ground
- 1/4 teaspoon garlic powder
- 1/2 lemon, Juice of
- 4 portobello mushrooms, sliced 1/4-inch thick
- 2 tablespoons olive oil
- 2 yellow onions, halved and thinly sliced
- Kosher salt and black pepper, freshly ground
- 4 ounces blue cheese, crumbled
- 1/3 cup mayonnaise
- 4 hoagie rolls, such as Martin's, split
- 1 cup arugula
- Balsamic vinegar, for drizzling
- Kosher salt
For the mushrooms, in a large bowl or a zip-top bag, whisk together the olive oil, Worcestershire sauce, salt, pepper, garlic powder and lemon juice. Add the mushrooms and toss to combine.
Marinate for 30 minutes to 1 hour.
For the blue cheese spread, mix the blue cheese and mayonnaise together in a small bowl.
Heat a grill pan over medium-high heat. Remove the mushrooms from the marinade and transfer to the grill pan. Cook until slightly wilted, browned and showing grill marks, 2-3 minutes per side.
Lightly toast the hoagie rolls on the grill pan then spread one side of each roll with the blue cheese spread. Top with mushrooms, caramelized onions and arugula. Drizzle lightly with balsamic vinegar, sprinkle with salt and serve.