
Flat iron steak marinade is great for adding additional flavors to the steak. At the same time, marinade works remarkably well as a steak tenderizer when you use the right ingredients. In this marinade recipe, you’ll find the list of ingredients and an explanation of how the ingredient impacts the flavor and the texture of the steak.
Flat steaks such as flank steak, skirt steak, and flat iron steak benefit from marinating. They take on flavors of the ingredients in marinade exceptionally well.
However, if you’re unfamiliar with flat steaks, you may ask, what’s a flat iron steak? It’s a steak cut carved from the cow’s shoulder. The shoulder is a well-exercised area of the cow; therefore, flat iron steak that is taken from the top muscle blade has a bold, beefy flavor. While steaks from well-worked muscles have a chewy texture, that’s not the case with flat iron steak. It’s the second most tender steak cut after filet mignon. Chefs and butchers from the University of Florida and the University of Nebraska came up with a solution to trim the connective tissue resulting in a fork-tender piece of steak.
Flat iron steak is a newer cut, and it’s not available in most supermarkets. Search for it online or at your local butcher shop. Flat iron steak is often known as oyster blade steak, butler’s steak, top chuck steak, shoulder top blade steak, top blade steak, or top blade filet.
The flat iron steak marinade recipe

The flat iron steak marinade recipe below will serve 4 people. Mix and preparing all ingredients will take around 15 minutes
Ingredients
- 2 pounds of flat iron steaks.
- 125 grams of olive oil: Olive oil help to seal in the juiciness and develop a brown exterior when searing the steak.
- 80 grams of lemon juice: Lemon adds flavor and tenderizes the steak.
- 80 grams of soy sauce: Soy sauce adds flavor and saltiness to the steak.
- 20 grams of balsamic vinegar: Balsamic vinegar help to balance out the flavors by adding a bit of acidity and sweetness.
- 50 grams of Worcestershire sauce: Worcestershire sauce is an incredible addition to red meat. It’ll add a unique flavor to the steak.
- 3 grams of freshly ground black pepper. Freshly ground black pepper will add an additional layer of flavor and spiciness.
- 3 grams of kosher salt. Kosher salt enhances flavor and helps tenderize the steak.
- 10 grams of minced garlic. Minced garlic adds garlicky flavor and spiciness to the steak.
- 15 grams of freshly chopped thyme. Thyme is an excellent aromatic for steak. It’ll add an additional layer of flavor.
- 15 grams of fresh rosemary chopped. Rosemary is an excellent aromatic that works with most steaks. It will add great flavor to the steak.
Instructions
- Mix olive oil, lemon, juice, soy sauce, balsamic vinegar, and Worcestershire sauce in a bowl. Add freshly ground black pepper and kosher salt.
- Peel garlic and wash thyme and rosemary. Mince peeled garlic and chop fresh thyme and rosemary. Add aromatics to the bowl with the rest of the ingredients. Mix everything together.
- Place flat iron steak in a zip lock bag or large container and pour over the marinade. Marinate for at least 4 hours or, ideally, overnight. Leaving steak marinated overnight will result in a flavorful piece of steak. Salt and acidity will tenderize the meat, while other ingredients penetrate the steak and add flavors. Marinating for less than 4 hours is not enough for meat to absorb all the flavors and tenderize.
How long to marinate flat iron steak?
How long it takes to marinate depends on the steak’s size. A large piece of meat will take longer to soak in all the marinade flavors and tenderize. A small steak cut will need less time. However, as a general rule, 4 hours is just enough to marinate flat iron steak. 2 hours of marinating will add additional flavor to the flat iron steak; however, it’ll not tenderize the steak as if it would overnight. Leaving steak to marinate overnight is ideal because steak will have enough time to tenderize and absorb the flavors.
How to cook marinated flat iron steak

You can cook a marinated flat iron steak using many different cooking methods. In fact, you can read this article about cooking flat iron steak and learn more about different ways to prepare the steak. Before cooking steak, removing as much marinade from the steak’s exterior as possible is important. It’ll help the steak to develop a caramelized crust. Flat iron steak can turn chewy if cooked past medium doneness. The marinade is not going to protect the steak from drying out. It’s best if flat iron steak is cooked medium rare (135° Fahrenheit/57°C).
One of the purest ways to prepare marinated flat iron steak is on a grill. Grilled flat iron steak has nice grill marks and flavor of the grill. Prepare the grill for two-zone cooking. Whether you’re using a charcoal grill or a gas grill doesn’t matter. Grill flat iron steak over medium-high heat until crust brown crust forms. Move the steak onto the indirect heat side of the grill and continue cooking to your liking.
Cooking marinated flat iron steak on a stovetop is fast and convenient. Pan-seared flat iron steak requires a heavy pan. Preheat the cast iron skillet over medium-high heat. Pour a few tablespoons of light olive oil and sear the steak for 1 1/2 minutes on each side. Turn the heat down to medium and continue cooking to your preferred doneness.
Sous vide steak flat iron steak is a sure way not to overcook the steak and to cook steak evenly. Sous vide marinated flat iron steak for 2 hours in a temperature-controlled bath and finish it off in a smoking hot cast-iron skillet. Here is a step-by-step guide on how to sous vide flat iron steak.
Broil marinated flat iron steak. Move the top rack of the oven 5 inches away from the broiler. Turn the broiler for 15-20 minutes before cooking to ensure it’s hot. Broil the steak turning every 3-4 minutes. Cook to your desired level of doneness.
Reverse-sear marinated flat iron steak to achieve tender texture and crispy exterior. Preheat the oven to 275° Fahrenheit to reverse sear flat iron steak. Cook the steak until the internal temperature is 30° Fahrenheit below the desired degree. Finish off the steak in a smoking hot cast-iron skillet until caramelized crust forms.
FAQ
What is the best way to tenderize a flat iron steak?
The best way to tenderize steak is with a dry brine, wet brine, meat mallet, marinade, or by slow cooking. However, to preserve the natural flavors of the meat and to tenderize the steak, it’s best to use kosher salt for tenderizing.