In a medium bowl, combine half the pecorino-romano with the bread crumbs, egg, chopped garlic, parsley and 2 tablespoons olive oil; set aside.
On a work surface, rub the flank steak with olive oil; generously season with salt and black pepper. Layer the ham, salami, mortadella and provolone, leaving a 1/2-inch border. Spread the reserved bread crumb mixture evenly over the provolone. Roll up the steak, jelly-roll style, to enclose the filling, then tie the roll in several places to secure the filling. Set aside.
In a large, ovenproof pot, cook the bacon over medium heat until the fat has rendered, about 7 minutes. Add the smashed garlic and the onion and cook until softened, about 3 minutes. Using a slotted spoon, transfer the bacon and onions to a bowl. Add the reserved meat roll to the pot and cook, turning, until browned on all sides, about 10 minutes. Add the wine and cook until reduced by half, about 10 minutes. Stir in the tomatoes, crushed red pepper and reserved bacon-onion mixture. Lower the heat, cover and simmer until cooked through, about 1 hour. Season to taste with salt and black pepper. Transfer the meat to a platter and let stand for about 15 minutes. To serve, thinly slice the braciola diagonally. Top each serving with the sauce and sprinkle with parsley and pecorino-romano.