01 -
Preheat oven to 375°F (190°C) to ensure an even bake for the stuffed steak.
02 -
Lay the flank steak flat on a cutting board. Using a sharp knife, slice the steak horizontally, taking care not to cut all the way through, and open it like a book to form a pocket for the stuffing.
03 -
In a large mixing bowl, blend together chopped spinach, ricotta cheese, shredded mozzarella, finely chopped sun-dried tomatoes, minced garlic, dried oregano, salt, and black pepper until thoroughly mixed.
04 -
Distribute the spinach and cheese mixture evenly into the pocket of the flank steak.
05 -
Roll the stuffed flank steak tightly from one short end to the other. Secure with kitchen twine at both ends and in the center sections to keep the filling sealed during cooking.
06 -
Heat olive oil in a large oven-safe skillet over medium-high heat. Sear the rolled steak on all sides for 4 to 5 minutes per side, ensuring a rich brown crust forms.
07 -
Transfer skillet to the preheated oven and cook for 20 to 25 minutes until steak reaches an internal temperature of 130°F (54°C) for medium-rare or preferred doneness.
08 -
Allow the steak to rest for 10 minutes after removing from the oven. Carefully remove kitchen twine, then slice the steak into 1-inch thick rounds. Serve warm.