01 -
Combine olive oil, soy sauce, red wine, Worcestershire sauce, Dijon mustard, lemon juice, 1 minced garlic clove, Italian seasoning, and ground black pepper in a bowl. Whisk thoroughly until blended.
02 -
Score both sides of the flank steak with shallow diagonal cuts spaced 1 inch apart. Place the steak in a large resealable plastic bag. Pour the marinade over the steak, seal the bag, and refrigerate for at least 8 hours or overnight, turning the bag occasionally.
03 -
Preheat oven to 350°Fahrenheit. Remove the steak from the marinade and pat dry with paper towels. Discard any excess marinade.
04 -
On a cutting board, sprinkle salt over the minced garlic clove. Use the flat side of a knife to mash them together into a smooth paste. Spread the garlic paste evenly over one side of the steak.
05 -
Evenly distribute the chopped onion and bread crumbs over the garlic paste. Layer with fresh spinach leaves, then shredded Swiss cheese, grated Parmesan cheese, and chopped sun-dried tomatoes.
06 -
Starting from one short end, carefully roll up the steak to enclose the filling. Secure the roll with kitchen twine or toothpicks at 1-inch intervals. Place the roll seam-side down in a baking dish.
07 -
Bake the steak roll uncovered for about 1 hour. The internal temperature of the center should reach at least 145°Fahrenheit when measured with a meat thermometer.
08 -
Remove from the oven and let rest for 5 to 10 minutes. Slice the roll crosswise into 1-inch thick portions and serve hot.