This Blue Cheese and Caramelized Onion-Stuffed Flank Steak is a delicious and impressive dish that is perfect for special occasions or a gourmet dinner at home. The flank steak is butterflied and stuffed with a flavorful mixture of blue cheese and caramelized onions, then rolled up and seared to perfection. The result is a tender and juicy steak with a rich and savory filling. Serve it sliced with a side of roasted vegetables or a fresh salad for a complete and satisfying meal.