Butterfly the steak by slicing it horizontally, stopping about ¾ inch from the other side. Open up the steak and pound it with a meat mallet to an even thickness.
1 1½ lb flank steak
Preheat oven to 350°F.
In a small bowl, mix together the vinegar, paprika, 2 tablespoons tomato paste, garlic, and 1 tablespoon of olive oil. Stir to form a paste. Measure out 1 tablespoon of the paste and set aside.
2 tbsp red wine vinegar, 2 tbsp smoked paprika, 3 tbsp tomato paste, 3 garlic cloves, 4 tbsp olive oil
Smear the remaining paste on the open side of the steak.
Layer the prosciutto, spinach, carrot, onion, bell pepper, and basil on top leaving about ½-inch border along the edges.
4 strips prosciutto, ½ cup fresh spinach, 1 medium carrot, ½ cup yellow onion, ½ cup roasted red bell pepper, ½ cup fresh basil
In a small bowl, combine the breadcrumbs, Parmesan cheese, thyme, 1 tsp salt, and ½ tsp pepper. Stir to combine and then sprinkle over the top of the filling on the steak.
¼ cup breadcrumbs, ¼ cup Parmesan cheese, 2 tsp dried thyme, Kosher salt and freshly ground black pepper
Roll the meat from the long end into a tight cylinder and tie every couple of inches with twine. Tuck in the ends of the rolled steak and then tie another strip of the twine lengthwise.
Brush the meat all over with olive oil and then liberally sprinkle all over with salt and pepper.
In a large oven-proof skillet, over medium-high heat, heat 2 tablespoons of olive oil. Add the meat and brown on all sides, about 5 minutes.
Place the skillet in the oven for 15 to 20 minutes. (Or, transfer to a roasting pan)
Remove the skillet (or pan) from the oven and then use tongs (or a metal spatula) to lift the meat and pour the white wine into the pan underneath the steak. (This will prevent sticking).
½ cup dry white wine
Place back in the oven and roast until an instant-read thermometer inserted into the center registers 130 to 135°F, about another 15 to 20 minutes.
Transfer to a carving board and tent loosely with aluminum foil to keep warm.
Add the Madiera (or Marsala) wine to the skillet (or pan) over high heat, and simmer, stirring to scrape up any browned bits from the bottom of the pan.
½ cup fortified wine
Whisk in the stock, Worcestershire sauce, and the remaining 1 tablespoon tomato paste and simmer, stirring often, until reduced by half, about 5 minutes.
1 cup beef stock, 1 tbsp Worcestershire sauce
Strain the sauce through a fine-mesh sieve.
Remove the strings from the meat and slice into 1/2-inch rounds.
Transfer to individual plates and ladle some of the sauce over the stuffed steak rounds. Serve at once, with more sauce on the side.