These fajitas are a classic way to enjoy flank steak. The steak is seasoned with a blend of spices, then grilled or broiled until cooked to your liking. Serve the steak in warm tortillas with sautéed bell peppers and onions, and your favorite toppings, such as salsa, guacamole, and sour cream. This recipe is perfect for a casual dinner party or a weeknight meal.