Preheat a large, high-rim cast iron pan over medium to high heat on your stove top (note: choose a cast iron pan with a tight fitting lid).
Generously season both sides of your Top of the Rib with Kosher salt and ground black pepper. Sear both sides of the Top of the Rib in the pan and then remove to the side until ready.
Meanwhile sautee your onions with the white pepper and fennel seed until translucent and fragrant, about 4 to 5 minutes. Add half of the water to the onions to ensure you scrape up the fond, or little brown bits, from the bottom of the pan. Place the seared Top of the Rib on top of the onions and add the remaining water, bringing the liquid up to about a quarter of the way up the meat. Place the tight fitting lid on the pan and reduce stove top to a medium to low flame and allow to cook for approximately 45 minutes or when the internal temperature reaches approximately 200-205F.
Slice rolls in half and toast your rolls until golden in a toaster or oven.
After the Top of the Rib has rested for about 15 minutes, remove and slice thinly against the grain of the meat. Replace the sliced meat back in with the onions and broth, cover with your Kosher non-dairy parve cheese and reheat until melted.
Build your Philadelphia-style Kosher “cheese” steak sandwiches with the onions, a little broth, and enjoy with your favorite toppings!
Bon Appétit!