Heat oil on medium-low. Add diced onions and cook until translucent, seasoning with salt and pepper. Move onions aside or remove, leaving the flavored oil.
Turn your Blackstone griddle to medium to medium-high heat. Place shaved ribeye in the oil. Using a scraper and spatula, pull and tear the meat apart as it cooks. Season with salt, pepper, and Cheesesteak seasoning.
Add sliced or diced American cheese to the meat, allowing it to melt. Mix in the onions, then divide the meat into three portions. Place a hoagie roll over each portion. Let sit for one minute. Using one hand to hold the roll and a spatula to lift, flip the cheesesteak off the griddle. Enjoy!
