Preheat the oven to 375 degrees Fahrenheit.

Place the flank steak on a cutting board. Butterfly the steak so it opens into an even layer. Cover with plastic wrap and gently pound it to approximately 1/2-inch thick.

Season both sides of the steak evenly with the salt, black pepper, garlic powder, and Italian seasoning.

Heat the olive oil in a large skillet over medium heat. Add the minced garlic and cook for about 30 seconds, until fragrant.

Stir in the chopped spinach and cook until wilted. Remove the skillet from the heat.

Add the mozzarella cheese, Parmesan cheese, roasted red peppers, and softened cream cheese to the spinach mixture. Stir until everything is evenly combined.

Spread the filling over the steak, leaving about a 1-inch border around the edges.

Starting from one of the long sides, roll the steak tightly into a log. Secure the roll with kitchen twine or toothpicks every 1 to 2 inches.

Place the stuffed flank steak seam-side down in a baking dish.

Roast for 35 to 40 minutes, or until the internal temperature reaches 135 degrees Fahrenheit for medium-rare or 145 degrees Fahrenheit for medium.

Remove the steak from the oven and let it rest for 10 minutes before slicing.

Slice into pinwheels and serve warm.