Grilled Marinated London Broil

Flank steak (sold in supermarkets as London broil) is a lean, beefy cut that lives or dies on two things: a flavorful marinade and a sharp knife at the end. This recipe nails both. The marinade is a balanced mix of dry red wine, balsamic vinegar, garlic, soy sauce, and a teaspoon of honey to round out the acidity. The wine and vinegar work together to tenderize the meat while the soy and honey deepen the savory crust.

Mashing the garlic into a paste with salt before blending is the technique most home cooks miss. The salt acts as an abrasive that breaks down the garlic cell walls, releasing way more flavor into the marinade than just chopping or pressing would. Don’t skip it.

The slice-against-the-grain step is non-negotiable. Flank steak has long, visible muscle fibers running in one direction. Cut parallel to those fibers and the meat is chewy; cut across them at a 45-degree angle and even a medium-well steak is tender.

Pro Tips

• Marinate at least 4 hours but ideally overnight; the acid in the marinade tenderizes over time.
• Bring the steak to room temperature before grilling for even cooking; cold meat sears unevenly.
• Let the steak rest a full 10 minutes after grilling so juices redistribute.
• Use an instant-read thermometer; pull at 130°F (54°C) for medium rare, 135°F (57°C) for medium.

Variations

• Swap balsamic for Worcestershire for a smokier marinade.
• Add 1 teaspoon fresh chopped rosemary or thyme to the marinade.
• Top sliced steak with a quick chimichurri of parsley, garlic, oil, and vinegar.