Flat Iron Steak Recipe

Use ingredients you probably already have in the kitchen to make a great marinade for this Flat Iron Steak Recipe. It turns an affordable piece of beef into something juicy, tender and super flavorful.

Try this flat iron steak recipe for a change

Unpopular opinion, but filet mignon is overrated. Yes, it’s very tender, but I don’t think it actually has that much flavor.

I much prefer a cheaper cut of meat, even if it needs a marinade. Cuts like flank steak and skirt steak can be SO tender and flavorful if prepared properly.

And recently, I’ve discovered something called a flat iron steak. Flat iron steaks are a more affordable and tasty way to get your beef fix compared to the pricier cuts.

Today, I’m sharing my favorite method for marinating and grilling a flat iron steak. It’s very likely you can make this with ingredients you already have in your kitchen! And, as you’ll see below, it’s VERY adaptable for what you have on hand.

What is a flat iron steak?

A flat iron steak is a cut from the shoulder of a cow. It is sometimes called a “top blade roast” or “patio steak.”

The entire top blade of the cow generally weighs between two and three pounds, and most butchers cut that into 4 flat iron steaks (about 12 ounces to a pound each).

Flat iron steaks generally have quite a bit of fat marbling running throughout them, which is what help makes them so tender and flavorful.

My favorite thing about flat iron steaks is how they are almost perfect rectangles, and are an even thickness throughout. That takes some of the guesswork out of grilling them!

Flat Iron vs Flank Steak

A flat iron steak comes from the shoulder area of a cow, while the flank steak comes from the abdominal area. Flat iron is known for its marbling and tenderness, while flank steak is leaner.

What is Flat Iron Steak good for?

Flat iron steak is a versatile cut that can be grilled, broiled, pan-seared or even sous-vide. It can be used in a variety of dishes, like fajitas, stir-fries, steak sandwiches, or simply enjoyed on its own.

Ingredients for Grilling Flat Iron Steak

• flat iron steak – you’ll need a 1 pound flat iron steak for this recipe. If you don’t see it out, ask your butcher!
• vegetable oil – or you can use olive oil here, but vegetable oil is much cheaper and I think it’s just fine for a marinade!
• soy sauce – there’s no salt in this marinade for flat iron steak, as all of the salt comes from the soy sauce. Don’t skip it!
• onion – you just need a small hunk of onion, roughly chopped. I usually use white or yellow onion, just depending on what’s in my fridge. I’ve even used a couple of green onions when I have them.
• garlic – adds a pungent depth of flavor to the marinade.
• orange juice – you can actually use ANY citrus juice here. I had oranges, but if you have lemons already on hand, use those. Limes work too!
• brown sugar – this adds sweetness to the marinade.
• chili powder – this adds a little mild heat to the marinade.
• cumin – this adds a warm, earthy flavor to the steak.
• giardiniera – optional, but one of my favorite garnishes for this cut of steak. I buy a jar of prepared mild (but you could do hot if you prefer) giardiniera, which is a pickled Italian relish made with peppers, celery, carrots and cauliflower. I roughly chop it and spoon it over the steak for serving.
• flaky sea salt – I prefer Maldon brand, and I can’t eat a steak without a sprinkle of it!

How to cook a Flat Iron Steak on the Grill

1. BLEND. Place all of the marinade ingredients in a blender and blend until smooth.
2. MARINATE. Place the steak in a shallow baking dish or zip-top bag and pour the marinade over the steak. Refrigerate at least 4 hours or up to overnight, turning once if possible.
3. ROOM TEMP. Remove the steak from the marinade and allow the excess marinade to drip off. Discard the marinade. Bring the steak to room temperature for 30 minutes before cooking.
4. GRILL. Preheat your grill for directing grilling over medium-high heat. Transfer the steak to the grill and cook 4 minutes, turning once halfway through.
5. FINISH COOKING. Reduce the grill heat to medium and continue cooking 6 to 8 minutes longer or until the center of the steak reaches 130 degrees F for medium rare, turning occasionally.
6. REST. Transfer the steak to a plate and cover lightly with foil. Let stand 5 minutes before thinly slicing across the grain.
7. SERVE. Serve the sliced steak garnished with giardiniera and flaky salt.

How long to marinate flat iron steak

It’s best to marinate flat iron steak for at least four hours so that the flavors can start to soak into the meat, and the acidity can tenderize the steak.

You can also marinate overnight! However, try not to marinate longer than 24 hours if you can help it.

After TOO long, the acid in this flat iron steak marinade recipe will start to “cook” the beef, and the steak will be a little tough once you grill it.

A little secret about this flat iron steak marinade recipe

My little secret is that I don’t measure anything when making this marinade (or any marinade for that matter). Well, except the one time I measured so that I could include measurements in the recipe card below.

But every other time, I literally just eyeball every ingredient. Life is too short to have to clean a bunch of measuring cups and spoons for a marinade for flat iron steak.

The exact ingredient amounts aren’t important here. As long as the general proportions are correct, the end result will be delicious.

So, go ahead, use a chunk of onion, a few squeezes of orange, a spoonful of brown sugar, and some dashes of spices. Honestly, you don’t need to measure anything for this flat iron steak marinade recipe.

How to garnish Grilled Flat Iron Steak

A perfectly grilled flat iron steak doesn’t really NEED much aside from a sprinkle of flaky sea salt.

But, I also love a little something acidic served with it to cut through the fatty richness of the meat.

I often serve it with a drizzle or balsamic vinegar reduction or a spoonful of chimichurri sauce made with both red wine vinegar and lemon juice.

When I don’t have either of those on hand, my favorite shortcut garnish for grilled steak is jarred giardiniera.

Giardiniera is an Italian relish of pickled vegetables. It is usually made with peppers, celery, carrots and cauliflower.

You can buy a spicy version, but I like the mild. I buy the Delallo brand. It is intensely bright and fresh and vinegary. I’m sure there are lots of other brands that are good, too.

I just give the giardiniera a rough chop and spoon it over the sliced steak. It doesn’t get any easier!

What to serve with this flat iron steak recipe

If it’s winter, I like to pair flat iron steak with a potato side dish and a vegetable. If it’s summer, I’ll choose a vegetable and a cold pasta or potato salad. Below, I’ve made a choose-your-own-adventure so you can round out your meal.

What other steaks can you use this marinade for?

I also love this flat iron steak marinade recipe for flank steak, skirt steak and hanger steak. All of these cuts are relatively inexpensive, can be tenderized very well with a simple marinade, and are full of flavor.

How to store Grilled Flat Iron Steak

If you have leftovers of grilled flat iron steak, allow them to cool to room temperature. Then, place them in an airtight container and refrigerate up to 3 days. You can also freeze up to 3 months.

Grilling Flat Iron Steak FAQs