Blog
Flat Iron Steak Recipe: Tender and Ready in 15 Minutes
This flat iron steak recipe is the fastest way to a steakhouse-style dinner on a weeknight. Flat iron is a well-marbled, evenly thick cut from the beef shoulder that is naturally tender and full of flavor. A quick garlic, soy and balsamic marinade seasons it in as little as 30 minutes, and the steaks sear in a hot skillet in about 10 minutes. Slice against the grain and dinner is ready.
Below you’ll learn what a flat iron steak is, how it compares to top blade steak, how to cook it in a skillet, under the broiler or on the grill, and the doneness temperatures to aim for. The printable recipe card is at the bottom of the page.
What Is Flat Iron Steak?
Flat iron steak comes from the top blade, a muscle in the shoulder (chuck) of the cow. This muscle has a thick line of tough connective tissue running through its center. Butchers cut along both sides of that line to remove it, leaving two flat, even steaks, usually about 1 inch (2.5 cm) thick and 8 to 12 oz (225 to 340 g) each. The name comes from their shape, which looks a bit like an old-fashioned clothes iron.
Because it comes from a muscle that does little work, flat iron is unusually tender for a shoulder cut, and it has plenty of marbling for a rich, beefy flavor. It is often described as one of the most tender steaks after tenderloin, at a much lower price.
Flat iron vs top blade steak
Both come from the same muscle. Top blade steak is cut across the muscle, so each steak still has the line of gristle running down the middle. It is tasty but chewier, unless you cut around the gristle. Flat iron has that gristle removed. If you buy top blade steaks, you can turn them into flat iron pieces by cutting along both sides of the center line.
Why You’ll Love This Flat Iron Steak Recipe
- Fast: about 10 minutes in the pan after a short marinade.
- Tender and juicy without the price of ribeye or strip.
- Even thickness means it cooks evenly, edge to edge.
- Big flavor from a simple marinade made with pantry staples.
Ingredients for Flat Iron Steak
- Flat iron steaks, 2 (about 1½ lb / 680 g total), about 1 inch (2.5 cm) thick.
- Olive oil, 3 tablespoons (45 ml), for the marinade.
- Soy sauce, 2 tablespoons (30 ml). It seasons the meat and helps it brown.
- Balsamic vinegar, 1 tablespoon (15 ml).
- Dijon mustard, 1 tablespoon.
- Garlic, 3 cloves, grated or minced.
- Fresh rosemary, 1 teaspoon, finely chopped (or ½ teaspoon dried).
- Black pepper, ½ teaspoon.
- Diamond Crystal kosher salt, ½ teaspoon, for just before cooking.
- Neutral oil, 1 tablespoon (15 ml), such as avocado or canola, for searing.
Equipment You Need
- A large cast-iron or heavy stainless steel skillet
- A zip-top bag or shallow dish for marinating
- Tongs and an instant-read thermometer
- A cutting board and a sharp knife for slicing
How to Make Flat Iron Steak (Step by Step)
1. Marinate in the refrigerator
Whisk the olive oil, soy sauce, balsamic vinegar, Dijon, garlic, rosemary and pepper in a bowl. Put the steaks in a zip-top bag or shallow dish, pour in the marinade and turn to coat. Refrigerate for at least 30 minutes and up to 8 hours. Always marinate meat in the refrigerator, not on the counter.
2. Take the steaks out early
Remove the steaks from the marinade about 20 minutes before cooking and discard the used marinade. Pat the steaks dry with paper towels; a dry surface browns much better. Sprinkle both sides lightly with the kosher salt.
3. Heat the pan
Heat the skillet over medium-high heat for 3 to 4 minutes, then add the neutral oil. When it shimmers, the pan is ready. Use medium-high rather than your hottest setting, because the soy sauce and balsamic in the marinade brown quickly.
4. Sear
Lay the steaks in the pan, leaving space between them. Cook without moving for 4 to 5 minutes, until a deep brown crust forms. Flip and cook 3 to 5 minutes more on the second side.
5. Check the temperature
Insert a thermometer into the thickest part from the side. For medium-rare, remove the steaks at 125 to 130°F (52 to 54°C); for medium, at 135 to 140°F (57 to 60°C). USDA recommends cooking beef steaks to 145°F (63°C), followed by a 3-minute rest. Flat iron is best between medium-rare and medium.
6. Rest and slice
Move the steaks to a cutting board and rest them for 5 minutes. Then slice about ½ inch (1.3 cm) thick, against the grain. Flat iron’s grain runs along the length of the steak, so cut across it, at a slight angle.
Flat Iron Steak Doneness Temperatures
| Doneness | Remove from heat at | After resting |
|---|---|---|
| Medium-rare | 125 to 130°F (52 to 54°C) | 130 to 135°F (54 to 57°C) |
| Medium | 135 to 140°F (57 to 60°C) | 140 to 145°F (60 to 63°C) |
| USDA recommended | 145°F (63°C) | Rest at least 3 minutes |
Medium-rare and medium are below USDA’s recommendation for whole cuts of beef. See the FoodSafety.gov safe minimum internal temperature chart for the official guidance.
Other Ways to Cook Flat Iron Steak
Under the broiler
Set an oven rack about 4 inches (10 cm) below the broiler and heat the broiler for 5 minutes. Put the marinated, patted-dry steaks on a foil-lined rimmed baking sheet and broil for 4 to 6 minutes per side, checking the temperature early.
On the grill
Heat a grill to high, about 450 to 500°F (230 to 260°C), and oil the grates. Grill the steaks for 4 to 5 minutes per side over direct heat. For a dry-rub, herb-butter approach on the grill, see our bavette steak recipe, which works just as well with flat iron.
Butter-basted in a pan
Skip the marinade, season with salt and pepper, and baste with butter, garlic and thyme in the last 2 minutes, as in our Denver steak recipe. Denver steak comes from the same shoulder area.
Tips for the Best Flat Iron Steak
- Pat it dry after marinating. A wet steak steams and turns gray instead of forming a crust.
- Don’t marinate too long. Up to 8 hours is plenty. Longer, and the acid and salt can make the surface mushy.
- Want a sauce? Never pour the used raw marinade over cooked meat. Set some fresh marinade aside before adding the raw steak, or bring the used marinade to a full boil for at least 1 minute before using it.
- Slice against the grain into thin strips for the most tender bite.
- Cook to temperature, not time. Steaks vary in thickness, and a thermometer takes the guessing out.
Marinade Variations
- Fajita style: olive oil, lime juice, garlic, 1 teaspoon chili powder and ½ teaspoon cumin. Slice thinly and serve in tortillas with peppers and onions.
- Korean-inspired: soy sauce, 1 tablespoon brown sugar, 1 teaspoon toasted sesame oil, grated ginger, garlic and 1 to 2 teaspoons gochujang. Watch the heat, as the sugar browns fast.
- Lemon herb: olive oil, lemon zest and juice, garlic, oregano and thyme. Add the salt just before cooking.
What to Serve With Flat Iron Steak
- Mashed potatoes, roasted potatoes or fries
- Roasted asparagus, green beans or a big green salad
- Garlic bread or crusty rolls
- Rice and stir-fried vegetables, since the soy marinade pairs well with them
How to Store and Reheat
- Raw flat iron steak keeps 3 to 5 days in the refrigerator, or about 4 to 12 months in the freezer for best quality.
- Cooked steak: refrigerate within 2 hours and eat within 3 to 4 days.
- Reheat slices gently in a skillet with a splash of broth for 1 to 2 minutes, or enjoy them cold on salads and sandwiches. Our leftover steak recipes have more ideas.
Storage times follow the FoodSafety.gov cold food storage chart.
Flat Iron Steak FAQs
Is flat iron steak tender?
Yes. Once the center gristle is removed, flat iron is one of the most tender cuts from the shoulder, especially when cooked to medium-rare or medium and sliced against the grain.
How long do you cook a flat iron steak?
About 4 to 5 minutes on the first side and 3 to 5 minutes on the second side in a hot skillet for a 1-inch steak. Use a thermometer: 125 to 130°F (52 to 54°C) for medium-rare, or 145°F (63°C) to follow USDA guidance.
Do I have to marinate flat iron steak?
No. It’s tender enough to cook with just salt and pepper. The marinade adds flavor and helps it brown.
Is flat iron the same as top blade steak?
They come from the same muscle. Top blade still contains the center line of gristle, while flat iron has it removed.
What is a good substitute for flat iron steak?
Denver steak, sirloin, hanger or skirt steak all work with this marinade. Adjust the cooking time for thinner or thicker cuts.
Flat Iron Steak Recipe Card
Calories are an estimate per serving based on USDA FoodData Central values for cooked beef shoulder steak plus the part of the marinade that stays on the meat. Looking for a different cut or a full spice rub? Try our homemade steak seasoning, see all our steak recipes, or season a chuck roast with our pot roast seasoning.
Marinated Flat Iron Steak
Ingredients
Equipment
Method
- Whisk the olive oil, soy sauce, balsamic, Dijon, garlic, rosemary and pepper. Coat the steaks and marinate in the refrigerator 30 minutes to 8 hours.
- Remove the steaks 20 minutes before cooking, discard the used marinade, pat dry and sprinkle with the salt.
- Heat a heavy skillet over medium-high heat 3 to 4 minutes, then add the neutral oil.
- Sear the steaks 4 to 5 minutes without moving, flip, and cook 3 to 5 minutes more.
- Remove at 125 to 130°F (52 to 54°C) for medium-rare or 135 to 140°F (57 to 60°C) for medium. USDA recommends 145°F (63°C) plus a 3-minute rest.
- Rest 5 minutes, then slice 1/2 inch thick against the grain.
