Stabilize your grill at 525°F. Have a grill grate on one side of the Divide and Conquer system and a Cast-Iron Half Moon Griddle or skillet on the other side.
Season the outside of your ribeye with a heavy hand. Place the wood chunk in the hottest portion of the coals to attain combustion and clean smoke. Place the ribeye on the grill grate and close the dome to begin “Smoke Searing."
Smoke the steak for 5 minutes, then open the dome and flip the steak. While the dome is open, place the sliced onions, mushrooms and bell peppers on the cast iron griddle. Allow the steak to continue smoke searing, but keep an eye on the vegetables. Toss vegetables with a bit of olive oil or duck fat spray, season with the Brisket Seasoning and using 2 spatulas, gently toss the vegetables so they are thoroughly mixed and evenly caramelized. Close the dome and allow the steak to finish smoking and the vegetables to finish.
Once the ribeye has a nice smoke-seared bark (but still rare) and the vegetables are done, remove both from the grill. Slice the ribeye into thin slices. Assemble sandwich while hot, and enjoy!