Preparation Steps

• Pat the flank steak dry and trim any excess surface fat; lightly score the surface in a crosshatch pattern to help the marinade penetrate.
• Whisk soy sauce, olive oil, lime juice, brown sugar, minced garlic, salt, black pepper, red pepper flakes, and cumin in a bowl.
• Place steak in a large zip-top bag or shallow dish and pour in the marinade. Seal and refrigerate at least 30 minutes and up to 8 hours, turning once.
• Preheat the grill to high heat (about 450 to 500°F). Clean and oil the grates with high-heat oil.
• Remove steak from marinade, letting excess drip off; pat lightly dry for better searing.
• Grill the steak for 4 to 6 minutes per side for medium-rare, or until an instant-read thermometer reads 130 to 135°F.
• Transfer to a cutting board, tent loosely with foil, and rest 10 minutes. Slice thinly against the grain and garnish with parsley.