Portobello-Steak Sandwich

2 teaspoons extra virgin olive oil
1 small onion, sliced
4 large portobello mushrooms, stems removed, sliced
6 oz cremini mushrooms, stems removed, sliced
2 teaspoons dried orgeno
1/2 teaspoon ground pepper
1/8 teaspoon sea salt
1 tablespoon all-purpose flour
1/4 cup vegetable broth
1 tablespoon soy sauce
3 ounces thinly slice provolone cheese
4 crunchy crusted small rolls

1. Heat the oil in a large skillet over medium heat. Add the onion and cook, stirring often until soft and browning. Add mushrooms, oregano, ground pepper and salt, and cook. Stirring often until the vegetables are tender and wilting.
2. Reduce heat to low, sprinkle the flour over the vegetables and stir until completely incorporated. Stir in the broth and soy sauce, bring to a simmer and cook for 1 to 2 minutes or until the mixture thickens just a bit. Remove from heat, lay the cheese over the top, cover and set aside for cheese to melt.
3. Divide mixture into 4 portions and serve on the rolls.