Start by pulling out all your ingredients. Have them at arm's length; it makes the process smoother. Since the entire marinade is made in one bowl, there’s no need to fuss over multiple dishes.

In a medium mixing bowl, combine the balsamic vinegar, olive oil, Worcestershire sauce, soy sauce, and Dijon mustard. Whisk these together until they are well blended. The marriage of these ingredients offers a sweet and savory base for your steak.

Next, add the minced garlic and red pepper flakes into the mixture. Both add layers of flavor and a touch of heat that enhances the overall taste of the steak. Give it another good whisk to ensure everything is evenly distributed.

Finally, season the marinade with a pinch of salt and freshly ground black pepper. Remember, the soy sauce and Worcestershire sauce already have salt, so go easy on it. Taste the marinade and adjust the spices as needed based on your preference. Whisk one last time before you’re ready to move on.

Place your steak in a large resealable plastic bag or an airtight container. Pour the marinade over the meat, and make sure it’s well-coated. Seal it up and refrigerate for at least 30 minutes. If time allows, let it marinate for several hours, or even overnight for maximum flavor. The longer, the better!