1/3 cup mayonnaise
8 ounces sliced Provolone cheese
Preheat the oven to 375 degrees. Season the steak with half the salt and pepper and all of the canola oil.
Heat a cast iron skillet over high heat and cook the steak for 2 minutes without stirring or turning. Add Worcestershire sauce and stir.
Remove from skillet and add butter, green peppers, onions, mushrooms and remaining salt and pepper. Cook for 3-4 minutes or until lightly browned.
Spread mayonnaise on both halves of bread.
Cover with half the provolone cheese, then add the steak and vegetables with the rest of the cheese on top.
Bake for 15 minutes on the middle rack until golden brown.