Season the chicken cutlets with salt, pepper, and a good bit of Blackstone Cheesesteak Seasoning on both sides.
Add 2 tablespoons of olive oil to the hot griddle and cook the chicken for 3 minutes per side.
Add a bit more olive oil next to the chicken and add the onions, bell peppers, and mushrooms with a bit more Blackstone Cheesesteak Seasoning. Toss to evenly coat and cook for 3-5 minutes.
Once the chicken is nearly finished, using your spatulas or a knife and cut the chicken into bite-sized pieces. Make 4 even piles of chicken and add some of the veggies over the tops of each. Add a couple of pieces of pepper jack cheese over each stack and cover to melt.
In a small bowl, mix the ranch and buffalo sauce evenly and add to the bottom of each hoagie roll. Add the chicken stacks to the hoagie rolls, slice, and serve hot.