Savory, juicy, and tender steak you will want on repeat! This marinade for flat iron steak is easy to make and works great on almost any cut of steak.
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It's getting to be one of my most cherished times of the culinary year: grilling season! Today, I introduce to you a tasty new way to grill up a juicy and tender steak: my favorite flat iron steak marinade recipe!
This simple soy sauce marinade is made with common pantry staples to produce big flavor. Though the steak is best if marinated ahead of time, the results are worth it and the steps are simple.
Serve up this steak for a special weeknight dinner, your next barbecue, or even Memorial Day or the 4th of July!
Save this recipe for later on Pinterest:
Flat iron steak vs. flank steak:
Though flat iron steak and flank steak can grill up very similarly, they are different cuts of steak. Flat iron comes from the chuck shoulder region of the cow, whereas flank steak is cut from the abdominal muscles.
Though traditionally flank steak was a more affordable cut of meat, it has gotten more expensive in recent years. Flat iron steak can be a more affordable way to enjoy grilled steak and is super tender and flavorful for the price.
Because of this, I most often make this marinade recipe with flat iron steak but it's also delicious made with flank steak.
Ingredients:
- Flat iron steak - this cut of steak can be found in the butcher department of most major grocery store chains and Whole Foods here in the U.S. If you can't find flat iron steak, the list of cuts of steak (below) are also delicious in this marinade!
- Reduced-sodium soy sauce
- Red wine vinegar
- Olive oil
- Red wine vinegar - adds some dimension to the marinade and tenderizes the steak.
- Minced garlic
- Dried rosemary
- Dried Italian seasoning
- Light brown sugar
- Dijon mustard - smooth Dijon mustard works best, but whole grain also works
Other cuts of steak for this marinade:
Though this is a delicious marinade for flat iron steaks, it's also delicious on:
- Flank steak
- Tri tip steak
- Sirloin steak
- Chuck eye steak
- ... and more!
How to make marinated and grilled flat iron steak:
For the complete recipe and measurements, scroll to the recipe card at the bottom of this post.
- Whisk together the soy sauce, vinegar, olive oil, salt, minced garlic, rosemary, Italian seasoning, Dijon mustard, brown sugar, and black pepper together until combined.
- Add the steak to the marinade. Turn to cover. Marinate the steak refrigerated for 6-12 hours, turning once or twice if possible.
- Preheat the grill to medium-high heat (or 375-400 degrees Fahrenheit).
- Add the steak to the grill, discarding the marinade. Grill the steak for 6 - 10 minutes, turning every 2 or 3 minutes, or until the steak has reached your desired degree of doneness.
Recipe pro-tips:
- Marinate the flat iron steak as long as possible. The longer the steak marinates, the more flavorful and tender the steak gets. You can even marinate the steak in the morning before the day gets started.
- Substituting fresh herbs. 1 ½ teaspoons minced fresh rosemary can substitute for the dried rosemary in the marinade.
- Preheat the grill. To grill the steak evenly and quickly, preheat the grill before adding the steak to it.
- Watch out for grill hot spots. If certain parts of your grill run hotter than others or cook the steak faster than others, rotate the steak evenly through those sections to prevent burning the steak and to help it cook evenly.
Freezing steak in the flat iron marinade:
Marinate the steak ahead of time or when you can grab flat iron steak on sale by freezing the steak in the marinade in a freezer-safe container for up to 3 months.
Defrost the steak in the marinade in the refrigerator for 24-36 hours, or until the steak is thawed through. Then grill the steak as directed.
Dietary adaptations:
- Gluten-free: to make this recipe gluten-free, substitute coconut liquid aminos or tamari sauce instead for soy sauce.
- Processed sugar-free: to make this recipe processed sugar-free, substitute maple syrup or honey for the packed brown sugar.
- Lower sodium: if you are salt sensitive or follow a low sodium diet, reduce the salt in the recipe to ¼ teaspoon or omit it entirely.
Storage directions:
Leftovers last refrigerated in a covered container for 4-5 days. They do not freeze well.
Tools needed to make this recipe:
More marinade recipes:
- Asian Tri-Tip Steak Marinade
- Spicy Honey Chicken Marinade
- Balsamic Marinated Chicken Thighs
- Mexican Chicken Marinade
- Asian Grilled Chicken
- Curried Yogurt Marinated Chicken
If you made and liked this recipe, don't forget to rate the recipe and let me know how it went for you in the comments! It always makes my day to hear from you!
Sharon says
Best marinade ever. During start of marinating on flank steak cooked few 1/8” slices in AF for 6 mins on 400 and they were awesome for steak sandwich. Definitely my go-to marinade in future. So delicious!!!
Mae's Menu says
Hi, Sharon!
I am so glad to hear that you liked it! Thanks for reviewing and sharing!
All the best,
Chelsea
Whitney Elton says
Can I also put this in the oven? We loved loved it on the grill. My husband wanted it for his birthday and it’s supposed to snow again sadly .
Mae's Menu says
Hi, Whitney! Great question, and such a bummer to hear about the snow for your husband's birthday! I probably wouldn't make this in the oven, as it wouldn't caramelize on the exterior like it does on the grill. A good alternative may be to cook it in a cast iron pan on the stovetop or even in the air fryer. If cooking with cast iron, drain off the marinade well so the sugars in it don't burn as the steak cooks. If in the air fryer, cook at 400 degrees Fahrenheit for 10-16 minutes, or until cooked through to your desired degree of doneness.
Hope this helps!
Best,
Chelsea