Open the hoagies · mayonnaise
Place each hoagie roll face down on the cool griddle so they are all the way open. That helps the bread brown more evenly later. Spread 1 Tbs mayonnaise on each hoagie (inside the roll).
Place each hoagie roll face down on the cool griddle so they are all the way open. That helps the bread brown more evenly later. Spread 1 Tbs mayonnaise on each hoagie (inside the roll).
Preheat the griddle to 350°F (or heat a large skillet over medium-high).
Slice the peppers, onions, and mushrooms if they are not already sliced. Place them in a medium bowl and set aside until you are ready to cook them.
Add 1 Tbs oil to the griddle and spread it around with your spatula. Place the hoagie rolls face down and brown for about 3 minutes, or until they are good and toasty.
Add another 1 Tbs oil and spread it around. Add the vegetables to the griddle and sauté for about 6 minutes. A timer helps so they cook through without getting too soft or over-caramelized.
Move the vegetables back into the bowl.
Add the last 1 Tbs oil to the griddle. Add the steak and chop and flip so it breaks into small pieces. Cook until browned and no pink remains—about 3–5 minutes.
With your spatula, scoot the steak into four piles about the same size as the hoagie rolls.
Divide the vegetables evenly over the four piles of steak.
Shingle 2 slices of provolone on each pile.
Let the piles sit on the griddle until the cheese is fully melted. Turn off the griddle. Carefully move each pile onto a waiting hoagie roll.