The flat iron steak, which sits on the shoulder blade next to the teres major, is great for marinating and grilling.
In a glass baking dish, season the steak with salt and pepper and rub with the olive oil. Spread the garlic, scallions and bay leaves all over the steak. Cover both sides of the steak with lemon slices. Cover and refrigerate for 24 hours. Light a grill and brush with vegetable oil. Scrape off the seasonings and bring the steak to room temperature. Season with salt and pepper and grill over moderately high heat until medium-rare within, 3 1/2 minutes per side. Transfer to a carving board and let rest for 5 minutes. Thinly slice across the grain and serve.