Ingredients:
2 lbs flank steak
Salt and pepper, to taste
2 tablespoons olive oil
4 tablespoons butter, divided
2 large onions, thinly sliced
2 cloves garlic, minced
1 tablespoon balsamic vinegar
1 tablespoon Worcestershire sauce
1/2 cup beef broth
8 slices provolone cheese
Instructions:
Preheat your grill to medium-high heat (about 375-400°F / 190-200°C).
Butterfly the flank steak by slicing it horizontally, leaving one long side intact, so you can open it like a book. Pound it to an even thickness with a meat mallet.
Season the inside of the flank steak with salt and pepper to taste.
In a large skillet, heat the olive oil and 2 tablespoons of butter over medium heat.
Add the thinly sliced onions to the skillet and cook, stirring occasionally, until caramelized, about 20-25 minutes.
Add the minced garlic to the skillet and cook for an additional 1-2 minutes, until fragrant.
Stir in the balsamic vinegar and Worcestershire sauce, scraping up any browned bits from the bottom of the skillet.
Pour in the beef broth and simmer until the liquid has evaporated and the onions are soft and jammy. Remove from heat and set aside.
Spread the caramelized onion mixture evenly over the inside of the butterflied flank steak.
Place the provolone cheese slices evenly over the onion mixture.
Starting from one long side, tightly roll up the flank steak into a log.
Using kitchen twine, tie the steak roll at 1-inch intervals to secure it.
Cut the steak roll crosswise into 1-inch thick pinwheels.
Season the pinwheels with additional salt and pepper, if desired.
Grill the pinwheels over direct heat for 4-5 minutes per side, or until they reach your desired level of doneness.
Remove the pinwheels from the grill and let them rest for a few minutes before serving.
Serve the French Onion Steak Pinwheels hot, and enjoy!