01 - In a medium mixing bowl, whisk together soy sauce, olive oil, Worcestershire sauce, balsamic vinegar, and lemon juice until thoroughly blended.
02 - Add minced garlic, Dijon mustard, brown sugar, black pepper, rosemary, and onion powder to the bowl. Whisk until the mixture is homogenous.
03 - Place steaks in a large resealable plastic bag or shallow dish. Pour the marinade over the steaks, ensuring each piece is fully coated.
04 - Seal the bag or cover the dish and refrigerate for at least 2 hours, or up to 24 hours for maximum flavor and tenderness. Turn steaks occasionally if possible.
05 - Remove steaks from the marinade, pat them lightly with paper towels, and discard any remaining marinade. Proceed to grill, pan-sear, or broil the steaks to your preferred doneness.