If you have a Blackstone grill, preheat it to medium-high heat. This step is crucial as it helps in achieving that perfect sear on the meat. If you’re using a regular skillet, make sure it’s well-heated before you start cooking.

Add a drizzle of oil to the grill. If you choose to include onions, throw them on first. Cook until they’re caramelized and golden brown. This usually takes about 3-5 minutes. Stir them occasionally. They should be sweet and soft when finished.

Once the onions are done, push them to one side of the grill. Spread the thinly sliced ribeye on the other side. Season with kosher salt and freshly ground black pepper. Sprinkle in the garlic powder. Stir gently to combine. Cook for about 5 minutes or until it's no longer pink but juicy and tender.

As soon as the meat is cooked, lay your cheese slices over the ribeye. Let them melt beautifully, which typically takes around 2 minutes. If you're using Cheez Whiz, pour it directly over the meat.

While the cheese is melting, slice the hoagie rolls down the middle. Lay them cut side down on the grill to toast for about 1-2 minutes until they have a golden-brown color. This step adds a delightful crunch.

Once everything is ready, it’s assembly time! Use a spatula to scoop the cheesy ribeye mix onto the toasted hoagie rolls. If you cooked onions, pile those on top. Serve immediately and enjoy!