Set a skillet or Blackstone griddle/ flat top grill over medium heat (I used a 12 inch cast iron skillet and baked the scalloped potatoes in the same skillet). Add a tablespoon of the olive oil and the diced onion, green pepper, kosher salt, pepper, and steak seasoning. Cook 4 to 5 minutes, stirring a few times.
Add the minced garlic, diced shaved steak, Worcestershire sauce, more kosher salt, pepper, and steak seasoning blend and cook 3 to 4 more minutes. Remove from the skillet or griddle and set aside.
Add the remaining tablespoon of olive oil to a 12 inch cast iron skillet or casserole dish and brush evenly over the skillet and up the sides to prevent sticking.
Place a layer of the thinly sliced potatoes in the skillet or casserole dish, kosher salt and pepper, a layer of cheese slices, and the onions, peppers and steak. Repeat the layers a few times ending with a potato layer.
Carefully pour the heavy cream over the potatoes, use just enough to cover the potatoes. Sprinkle the mozzarella cheese over top.
Set the Traeger to 350 degrees. Place the skillet or casserole dish on the grill grate for about 1 1/2 hours.