Preheat oven to 375°F.
Heat the oil. Heat 1 tablespoon of olive oil in a 12-inch cast iron skillet over medium-high heat until the oil shimmers.
Cook the vegetables. Add the onion and both bell peppers, season with ½ teaspoon seasoning salt, ¼ teaspoon garlic powder, and ¼ teaspoon black pepper, and cook for 6 to 8 minutes, stirring occasionally, until tender and browned on the edges.
Set aside. Transfer the cooked peppers and onions to a clean plate.
Reheat the skillet. Place the skillet back over high heat and add the remaining 1 tablespoon of olive oil.
Cook the beef. Add the shaved ribeye and pull it apart with a wooden spoon as it cooks. Season with ½ teaspoon seasoning salt, ¼ teaspoon garlic powder, ¼ teaspoon black pepper, and the Worcestershire sauce, then sauté for 3 to 5 minutes until browned and fully cooked through.
Combine the filling. Turn off the heat, stir the cooked peppers and onions back into the beef, and spread the mixture into an even layer in the skillet.
Toast the rolls. Cut the hoagie rolls, place them cut-side up on a baking sheet, and bake for 4 to 5 minutes until warm and lightly toasted.
Melt the cheese. Lay the provolone slices across the top of the filling and cover the skillet with a lid or foil for 1 to 2 minutes, letting the residual heat melt the cheese.
Fill the rolls. Scoop the cheesy beef and vegetable filling into the toasted hoagie rolls and serve.