Whisk together the olive oil, Worcestershire sauce, soy sauce, Dijon mustard, brown sugar, garlic, Italian seasoning, salt, and pepper in a mixing bowl.

Place the London broil in a large resealable bag or a covered dish. Pour the marinade over the steak, ensuring it is evenly coated. Seal the bag or cover the dish and refrigerate for at least 4 hours or overnight.

Set your broiler to high heat. Position the oven rack 4-6 inches below the broiler. Line a baking sheet or broiler-safe pan with aluminum foil.

Take the steak out of the marinade, allowing any excess to drip off, and place it on the prepared pan. Discard the leftover marinade.

Broil the steak for 5-6 minutes on one side, then flip it and broil for another 3-4 minutes. For medium-rare, aim for an internal temperature of 130°F (54°C).

Take the steak out of the oven and let it rest on a cutting board for 10 minutes.

Slice the steak thinly against the grain. Serve immediately and enjoy!