01 -
In a large bowl, whisk together the olive oil, soy sauce, red wine, Worcestershire sauce, Dijon mustard, lemon juice, one clove of minced garlic, Italian seasoning, and black pepper until well combined.
02 -
Score the flank steak by making shallow diagonal cuts about an inch apart across the surface - this helps the marinade penetrate. Pop the steak into a ziplock bag, pour in the marinade, squeeze out the air, and seal it up. Let it hang out in the fridge overnight or at least 8 hours, flipping the bag occasionally when you think of it.
03 -
Heat your oven to 350°F. Take the steak out of the marinade, pat it dry with paper towels, and toss the leftover marinade.
04 -
On your cutting board, sprinkle the salt over the remaining minced garlic clove. Using the flat side of your knife, mash and drag it across until you've made a smooth garlic paste. Spread this evenly over the top of your steak - this is your flavor foundation.
05 -
Sprinkle the chopped onion evenly over the garlic paste, then add a layer of bread crumbs. Arrange the spinach leaves to cover the surface, then top with an even layer of Swiss cheese, followed by the Parmesan, and finally the chopped sun-dried tomatoes.
06 -
Starting from one of the short ends, tightly roll up the steak like a jelly roll, keeping all those delicious fillings tucked inside. Tie it up with kitchen twine every inch or so, or secure with toothpicks if that's what you have. Place it seam-side down in a baking dish.
07 -
Slide the baking dish into your preheated oven and let it cook uncovered for about an hour. Check that it's done by inserting a meat thermometer into the thickest part - you're looking for at least 145°F for medium-rare.
08 -
Once done, let the steak rest on a cutting board for 5-10 minutes - this helps keep all those juices inside. Remove the twine or toothpicks, then slice into 1-inch thick pinwheels to serve.