Special equipment: a meat mallet; kitchen twine
For the braciola: Preheat the oven to 350 degrees F. Toss the pine nuts in a small skillet over low heat until lightly toasted, about 3 minutes. Cool and chop.
Combine the bread and 2 cups warm water in a medium bowl, then let soak until softened, about 5 minutes. Squeeze out the excess water, then add to a large bowl with the Parmesan, parsley, garlic, eggs, scallions and pine nuts and mix to combine well. Season with 1/2 teaspoon salt and several grinds of black pepper.
Set the flank steak on a cutting board. Use a knife to score the steak down the middle against the grain, cutting only halfway through its thickness. Working from the center out toward the edges, cut thin flaps from the score to the edge, like a gatefold. Pound with the flat side of a meat mallet to an even thickness of about 1/2 inch. Sprinkle both sides of the steak with salt and pepper.
Layer the prosciutto over the steak, leaving a 1-inch border around the edges. Layer the provolone over the prosciutto. Pat the stuffing in an even layer over the provolone. Roll the steak around the fillings like a jelly roll, from short side to short side. Tie closed at 2-inch intervals around the circumference with kitchen twine. Tie 1 more piece of twine lengthwise around the meat. Sprinkle the outside of the braciola with salt and pepper.
For the sauce: Heat the oil in a large Dutch oven over medium heat. When the oil is hot, brown the braciola on all sides, about 6 minutes total. Remove to a plate. Add the onion and cook until softened, about 4 minutes. Add the garlic and cook until softened, about 1 minute. Pour in the red wine and bring to a boil. Reduce the wine until almost gone, then add the tomatoes, oregano and bay leaf. Add the braciola back to the pot with enough water to come halfway up the sides of the braciola (1 to 2 cups). Bring to a simmer, then cover and bake until fork tender, 1 hour and 30 minutes to 1 hour and 45 minutes.
For serving: Remove the braciola to a cutting board and let rest 10 minutes. Meanwhile, bring the sauce to a simmer on the stove top. Stir in the parsley. Untie and slice the braciola into 6 thick slices on a slight bias. Spread about 1 1/2 cups sauce on a rimmed platter and arrange the braciola slices on top. Add the cooked pasta to the simmering sauce and toss to coat, adding up to 1/2 cup pasta cooking water if it seems dry. Sprinkle with the Parmesan, then toss and serve alongside the braciola.
Copyright 2017 Television Food Network, G.P. All rights reserved.