Preheat your oven to 350°F (175°C).

Pound the flank steak to about ¼ inch thick between plastic wrap.

In a mixing bowl, combine spinach, Parmesan, breadcrumbs, sun-dried tomatoes, garlic, oregano, basil, salt, and pepper.

Spread filling evenly on each steak slice, roll tightly, and secure with twine or toothpicks.

Sear the rolls in a skillet with olive oil for 2-3 minutes per side.

Pour marinara sauce over the beef rolls in the skillet.

Transfer to the oven and bake for 35-40 minutes.

Let the rolls rest for 10 minutes before slicing.

Serve topped with marinara sauce and garnish with parsley.