Red meat lovers rejoice! Family-style Grilled Flat Iron Steak is a tender, juicy meaty masterpiece. Easy to prep and easy to cook, this cut yields big bold flavor from garlic, Dijon, and lemon – plus, just the right amount of char. Flat Iron is filet mignon’s delicious, budget-friendly cousin – so let’s learn how to cook it to perfection!

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Let this serve as your reminder that less expensive cuts of meat are worthy of your attention. Now I am well aware that an A5 Kobe filet is probably as close to eating unicorn that we’ll ever get, (not that I’d eat a unicorn if they existed, but you catch my meaning), but if you’re a “flat iron steak isn’t as good as filet” kind of snob, then give me 5 minutes to convert you.
One factor to keep in mind is that different cuts need to be handled and cooked differently. Not all steaks should be grilled at the same temp for the same time: some are better marinated, some are better cooked from different starting temps, and some need a deep tissue massage. Sure, we take short cuts and approximate for the sake of expediency, but don’t judge the meat, judge the chef.
So when you get down to the tips section of this, or any other recipe worth its salt, don’t gloss over them. Trust that time and money were spent getting those times and temps right. And trust that if I did give a flat iron steak some shiatsu and sing it a lullaby before grilling it, and it resulted in the most flavorful hunk of beef ever, I would tell you so and definitely wouldn’t have bribed my husband not to release video of it on the internet.
What is Flat Iron Steak?
Flat iron is a beautifully marbled cut of steak that comes from the shoulder and is the same grain as chuck.
Here’s what’s really important: flat iron steak is incredibly tender with terrific flavor. Think of it as the love-child between a filet mignon and a NY strip – at half the cost!
Omaha Steaks has a pretty thorough explanation of this marbly meat, but even better than that, it has some of its fun alternate names, like butler’s steak (rude!), feather blade steak, and oyster blade steak (fancy!).
Flat Iron Steak Marinade
Flat iron doesn’t need a marinade since it’s a pretty flavorful cut of steak all on its own thanks to its marbling (“marbling” are the fat ribbons throughout a cut of beef).
But I’d argue that MOST steaks (with the exception of a really great filet) benefit from a bit of marinating that will compliment the flavor and create a golden brown and flavorful crust. This is our favorite marinade for flat iron steaks:
- GARLIC: break down into a paste; this is easiest with a mortar and pestle, but finely chopping and smashing with the flat edge of a chef’s knife does a great job too!
- OLIVE OIL: not extra virgin; avocado oil also works great!
- DIJON MUSTARD: check your labels if paleo, Whole30, or keto and be sure to choose a clean, sugar-free brand.
- LEMON JUICE: fresh is best! especially since you’ll also need the zest.
- LEMON ZEST: use a microplane for zesting the peel.
- KOSHER SALT: all of our recipes are tested with kosher salt; if using table salt or fine sea salt, halve the amount.
- GROUND PEPPER
How to Grill Flat Iron Steak
Rub it in, why don’tcha! A zesty marinade lends flavor and crust to this perfectly grilled Flat Iron Steak. Preparation is easy, but precise, so make sure you’ve got plenty of time to marinate and bring back up to room temperature before grilling. Serve your flat iron steak family-style with your choice of sides.
For a condensed post, click to view the web story for this flat iron steak recipe!
- MAKE THE MARINADE. Smash the garlic into a paste-like consistency using a mortar and pestle or your chef’s knife. Whisk the garlic with olive oil, dijon mustard, lemon juice, lemon zest, salt, and pepper..
- MARINATE. Coat the steak with the marinade; cover and place in the fridge to marinate at least 4 hours.
- BRING TO ROOM TEMPERATURE. Remove the steak from fridge 1 hour prior to cooking to bring to room temperature.
- HEAT GRILL. Heat a gas grill to high heat or prepare a charcoal grill.
- SEAR. Sear over high heat (or direct heat on a charcoal grill) 2 minutes per side with the lid OPEN.
- GRILL. Reduce grill heat to medium (or move steaks to indirect heat on a charcoal grill). Cook an additional 3-5 minutes per side with the lid CLOSED, depending on your desired final temperature (see notes).
- REST. Remove from grill. Rest 5-10 minutes on a cutting board, then slice against the grain.
Tips for Perfect Grilled Steak!
- Bring the steaks to room temperature first – pull them out of the fridge 30-60 minutes prior to grilling. This will help the interior cook more evenly.
- Sear the steaks over high heat (2 minutes per side) with the LID OPEN.
- Finish cooking the steaks over medium heat (3-5 minutes per side) with the LID CLOSED; closing the lid essentially creates a convection oven environment, and will allow the steaks to cook more efficiently at the lower temperature.
- Always check the internal temperature using an instant read thermometer.
- Rest your steaks 5-10 minutes to allow the juices to settle.
- Slice against the grain for tender bites. Need more info? Here’s a great article from The Kitchn with everything you need to know!
Temperature Guide
Don’t grill above medium! Flat iron is a very tender cut that quickly loses flavor and texture the longer it cooks. Pull the steaks once the internal temperature registers no higher than 130°F.
- RARE: cook to 120°F, rest 5 minutes; final temperature will rise to approximately 125°F.
- MEDIUM RARE: cook to 125°F, rest 5 minutes; final temperature will rise to approximately 130°F.
- MEDIUM: cook to 130°F, rest 5 minutes; final temperature will rise to approximately 135°F.
What to Serve with Grilled Steak
- Since your grill will already be at medium heat when the steak finishes, do a quick, simple vegetable, like Grilled Broccoli or Grilled Zucchini.
- We love a garlicky green bean with steak, and we’ve got them 3 ways: original Garlic Green Beans, with Bacon, and with Crispy Shallots.
- Can’t go wrong with Steak and Potatoes. Try crispy bites like our Rosemary Potatoes or these Garlic Parmesan Potatoes, or go all out with a Baked Potato!
- Lighten up with a bright pasta salad, like Mediterranean Orzo, or a leafy green salad, like our Grilled Peach Salad. Bonus, your grill is already set!
More Sizzlin Grilled Steak Recipes
- Grilled Steak Skewers with Dipping Sauce Trio
- Steak Fajita Salad
- Grilled Rosemary Flank Steak
- Skirt Steak Tacos
- Flank Steak Skewers
- Ultimate Steak Sandwich with Arugula and Pesto
Did you make this grilled flat iron steak? I’d love to know how it turned out! Leave a comment and a rating below.
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Recipe
Grilled Flat Iron Steak
Print Recipe Rate this Recipe Pin RecipeIngredients
- 1.5 lb flat iron steak
Marinade
- 4 cloves garlic
- 4 tbsp olive oil
- 1 tbsp dijon mustard
- 1 tbsp lemon juice
- 1 tsp lemon zest
- 1 tbsp kosher salt
- 1.5 tsp ground pepper
Instructions
- Peel the garlic cloves, then smash and roughly chop. Use the flat side of a chef’s knife to pulverize the garlic into a paste-like consistency. Alternatively, mash the garlic using a mortar and pestle.
- Transfer garlic to a small bowl. Add the olive oil, dijon mustard, lemon juice, zest, salt, and pepper. Mix until well combined.
- Rub the marinade evenly over all sides of the steak. Arrange on a plate, cover with plastic wrap, and marinate in the fridge 4-6 hours.
- Remove the steak from the fridge 1 hour prior to cooking to bring to room temperature.
- Heat a gas grill to high heat or prepare a charcoal grill for both direct heat and indirect heat.
- Gas Grill: Place the steaks on the grill in an even layer. Sear the steaks 2 minutes with the lid OPEN, flip the steaks, then sear 2 minutes more over high heat. Reduce the grill heat to medium and grill an additional 3-5 minutes per side with the lid CLOSED, depending on your desired final temperature (see notes).
- Charcoal Grill: Place the steaks on the grill over direct heat. Sear the steaks 2 minutes with the lid OPEN, flip the steaks, then sear 2 minutes more. Move the steaks away from direct heat; grill an additional 3-5 minutes per side with the lid CLOSED, depending on your desired final temperature (see notes).
- Remove the steaks from the grill and transfer to a cutting board. Rest 10 minutes, then slice against the grain.
Notes
- RARE: cook to 120°F, rest 5 minutes; final temperature will rise to approximately 125°F.
- MEDIUM RARE: cook to 125°F, rest 5 minutes; final temperature will rise to approximately 130°F.
- MEDIUM: cook to 130°F, rest 5 minutes; final temperature will rise to approximately 135°F.
Sherry Fuller
My family and I were absolutely amazed at how great this steak was. I looked at a lot of marinade recipes but chose this one because I had all the ingredients on hand. I had never seen these particular ingredients put together in a marinade. Despite your warning about not cooking your steak well done, this is the perfect marinade for those of us who like them that way. Somehow the marinade penetrates the entire steak and keeps it flavorful and juicy. This is next to impossible for a well done steak. This will be my go to marinade for steaks from now on. Thanks for such a fabulous recipe.
Danielle Esposti
Sherry, thank you for such a thoughtful review! I’m so glad you found your way here and found a marinade that works for you.