In a medium mixing bowl, whisk together olive oil, soy sauce, red wine, Worcestershire sauce, Dijon mustard, lemon juice, 1 minced garlic clove, Italian seasoning, and freshly cracked black pepper until well combined and smooth.

Pound the flank steak to a uniform 1/2-inch thickness using a meat mallet, ensuring an easy roll later. Make shallow diagonal cuts on both sides of the steak for enhanced flavor absorption. Place the steak in a resealable plastic bag and pour the marinade over it. Seal the bag tightly and refrigerate for at least 8 hours or overnight for optimal flavor.

About 30 minutes before you’re ready to bake, preheat your oven to 350°F (175°C).

Once marinated, carefully remove the flank steak from the bag and pat it dry with paper towels to remove excess marinade. Discard the marinade.

In a small bowl, mash 1 minced garlic clove with a pinch of salt to form a coarse paste. Evenly spread the garlic paste across the surface of the flank steak.

Sprinkle chopped onion, fine dry bread crumbs, fresh spinach, shredded Swiss cheese, grated Parmesan cheese, and chopped sun-dried tomatoes evenly over the steak.

Carefully roll the steak up tightly from one short end, making sure to keep the filling inside as you go. Once rolled, secure the pinwheel with kitchen twine or toothpicks, spacing them about 1 inch apart.

Place the dish in the preheated oven and bake for about 1 hour, or until the internal temperature of the pinwheels reaches 145°F (63°C).

Once done, remove the pinwheels from the oven and let them rest for 5-10 minutes before slicing. Slice the pinwheels into 1-inch thick pieces and serve warm.