COOK IT.
Preheat your flat top griddle to 375°F. If using a gas or charcoal grill, set heat to medium heat. For all other grills, preheat a cast iron skillet on grill grates.
Melt 1 tablespoon of butter and 1 tablespoon of olive oil on griddle. With a serrated knife, slice hoagie rolls 3/4 of the way through, then place face down onto the griddle and cook until toasted. Set aside.
Melt remaining tablespoon of butter and olive oil on the griddle. Add sliced onions and bell pepper and cook for 2 minutes, or until lightly caramelized. Move veggies to the lower-right corner of griddle to keep warm.
Season steak generously with Pit Boss Classic Steakhouse Rub, then place on griddle and cook for 3 minutes, stirring to brown all sides. Mix in caramelized onions and bell pepper.
Divide steak and onions into 4 portions on the griddle, then top each with 2 slices of provolone cheese. Let cheese melt slightly and transfer to a toasted hoagie roll using a bench scraper or metal spatula. Serve hot and enjoy!