Place the steaks in the freezer for 30 minutes. (This will help make them easier to thinly slice.)

Meanwhile, leaving the roll attached on one side, split the hoagie rolls in half lengthwise. Spread the softened butter over the cut sides of each roll.

Transfer the steaks to a cutting board and slice them against the grain at thinly as you can. Lay the slices on a piece of parchment paper and season with 1 teaspoon of salt and ½ teaspoon of pepper.

Heat 2 adjacent zones to medium-high heat and 1 zone to medium-low heat for 8 to 10 minutes.

Drizzle or squeeze the oil over the medium-high zones and spread with a spatula. Place the onions on the hot cooktop, season with ¼ tsp of kosher salt, and cook, tossing occasionally, until golden brown, about 5 minutes. Meanwhile, place the rolls buttered side-down on the medium-low zone and toast until golden brown, about 1 minute. Transfer to plates or a serving platter and turn off the medium-low zone.

Gather the onions to one medium-high zone on the griddle. Add the steak to the empty medium-high zone seasoned-side-down, and cook until browned on one side, about 1 minute, then. Flip, season with more salt and pepper, then toss the steak with the onions to combine.

Divide the steak and onions into 4 piles about the size of your rolls. Divide the cheese between the piles, cover with a steam dome, and let melt (or heat up in the case of Cheez Whiz), for about 1 minute.

Use a spatula to transfer each intact pile to a roll and serve. Enjoy!