Start by heating a large skillet over medium-high heat.
Then, add the vegetable oil and let it heat up.
Cook the sliced onions and green bell peppers until they turn soft and translucent.
Season with salt and pepper. Transfer to a plate and set aside.
In the same skillet, add the thinly sliced ribeye steak and cook until browned, breaking it apart as it cooks.
Split the hoagie rolls or sub buns open, spread them with butter, and toast them lightly on the griddle or skillet.
Divide the meat into two portions on the skillet.
Place the cooked onions and bell peppers over the meat.
Lay two slices of provolone cheese over each meat portion.
Once the cheese is melted, use a spatula to lift the meat and cheese and place it into the toasted hoagie rolls or sub buns.
Serve immediately with optional hot sauce or ketchup on the side.
