Preparation

1. To butterfly the steak: Using a long sharp knife, holding it parallel to the work surface, cut through one long side of the steak, stopping about 1/2 inch from the opposite side. Open the steak as you would a book. (Don’t worry if you made a hole or two in the meat, because it will be concealed when you roll up the steak.) Set aside.
2. Heat a large skillet over medium heat and add 1 tablespoon of the olive oil. Add the shallot and sauté until soft, about 3 minutes. Add the spinach and cook until just wilted, about 3 minutes. Transfer to a strainer.
3. When it is cool enough to handle, squeeze out all of the moisture from the spinach. You should have about 1 cup of spinach. Transfer to a medium bowl and stir in the bread crumbs and cheese. Season to taste with salt and pepper.
4. Place the steak on a sheet of plastic wrap with a long side of the steak facing you. Smear the spinach mixture evenly over the steak, leaving a 1-inch border along the edge farthest from you. Beginning with the side nearest you and using the plastic wrap as an aid, roll up the steak, gently pressing on the filling, then tie the rolled steak with butcher’s twine at 2- to 3-inch intervals. Season the outside with salt and pepper to taste.
5. Build a fire in a charcoal grill, leaving one side of the grill free of coals. Place the meat on indirect heat, turning occasionally, until an instant-read thermometer registers 125 degrees for medium-rare meat, about 30 minutes. When the meat has reached your desired doneness, Sear the roast on all sides directly over hot coals. Place a cast Iron pan on the coals and let come to medium-high temperature. Add butter, rosemary and roast basting quickly. Carefully remove from fire and add bourbon. Taking care to watch for flare ups return to heat and reduce by half. Let rest for at least 15 minutes before removing twine and carving into 1/2-inch slices. For easier slicing, let roast cool to room temperature, plate and drizzle with remaining sauce.