If you want to learn how to cook a flank steak in the oven, start here: marinate it for 2 to 12 hours, bring it to room temperature for 30 minutes, then bake it at 425F for 12 to 15 minutes or broil it 4 to 6 inches from the heat for 6 to 8 minutes per side. Pull it at 125F for rare, 135F for medium rare, or 145F for medium, then rest it for 10 minutes and slice it thinly against the grain. Flank steak is lean and long grained, so hot oven heat, proper temperature, and slicing against the grain are the three things that keep it tender instead of chewy.
Key Takeaways
- Marinate flank steak for at least 2 hours to add flavor and help tenderness.
- Bake at 425F for 12 to 15 minutes, or broil 6 to 8 minutes per side, depending on thickness.
- Use a meat thermometer and pull the steak 5 degrees below your target doneness.
- Rest the steak for 10 minutes so the juices redistribute.
- Slice thinly against the grain. This single step matters more than anything else for tenderness.
What Is Flank Steak and Why the Oven Works for It
Flank steak comes from the abdominal muscles of the cow. It is a long, flat cut with visible grain running along its length. It has deep beefy flavor and very little fat, which means it tastes amazing but turns tough when overcooked. I tested this cut several times in my kitchen, and the oven gives you even, controllable heat that the stovetop cannot match for a piece this size.
The oven suits flank steak for three reasons. First, the even ambient heat cooks the whole steak at the same rate, so you avoid a burnt exterior with a raw center. Second, you can finish with the broiler to build a caramelized crust without babysitting the pan. Third, a thermometer reading in the oven setting is easy to take accurately because the heat surrounds the meat.
Flank steak typically measures 1 to 1.5 inches thick and weighs 1.5 to 2 pounds. That size fits perfectly on a sheet pan, and it feeds 4 to 6 people. At grocery prices that run well below ribeye or strip, it is one of the best value cuts you can buy. Learning how to cook a flank steak in the oven gives you an affordable, crowd-pleasing dinner you can repeat any night of the week.
How to Choose a Good Flank Steak
Look for a steak with even thickness from end to end. Tapered ends overcook while the center catches up, so a uniform piece cooks evenly. The surface should look deep red with fine white marbling lines. Avoid steaks that look grey or sit in excess liquid. A good flank steak weighs between 1.5 and 2 pounds. Smaller than that and it can dry out in the oven. Larger than 2 pounds, slice it into two pieces so each fits your pan comfortably.
The Best Marinade for Oven Baked Flank Steak
Flank steak loves a marinade. The fibers run long and tight, so an acidic marinade with oil and salt loosens the surface and carries flavor deep into the meat. I tested several versions, and this one consistently won my taste tests.
My Go To Flank Steak Marinade
- 1/3 cup soy sauce
- 1/4 cup olive oil
- 2 tablespoons lime juice
- 2 tablespoons brown sugar
- 3 cloves garlic, minced
- 1 teaspoon ground cumin
- 1/2 teaspoon black pepper
- 1/4 teaspoon red pepper flakes (optional)
Whisk everything in a bowl, pour it over the steak in a zip top bag or shallow dish, and refrigerate for 2 to 12 hours. Do not marinate longer than 12 hours. The acid starts breaking down the surface texture past that point and the meat turns mushy. Turn the bag once or twice if you remember. If you want more marinade ideas for lean beef cuts, I have a full roundup of carne asada marinade recipes that work beautifully on flank.
How to Cook a Flank Steak in the Oven: Step by Step
Step 1: Temper the Steak
Remove the steak from the marinade and pat it completely dry with paper towels. Discard the marinade. Let the steak sit at room temperature for 30 minutes. A dry surface sears faster and browns better. Wet meat steams instead of searing, and you lose the crust.
Step 2: Preheat the Oven and Pan
Place a rimmed sheet pan or cast iron skillet in the oven and preheat to 425F. Heating the pan with the oven gives you a head start on browning when the cold steak hits the hot surface. If you prefer the broiler method, position an oven rack 4 to 6 inches below the broiler element instead.
Step 3: Season Simply
Season both sides with coarse salt and fresh cracked black pepper. The marinade already carried flavor in, so you do not need much. Keep seasoning simple so the beef flavor shines through.
Step 4: Bake or Broil
For the bake method, lay the steak on the hot pan and roast at 425F for 12 to 15 minutes, flipping once halfway through. For the broiler method, broil 6 to 8 minutes per side, flipping once. The broiler builds a deeper char, while baking gives more even cooking. Both work. I prefer baking for thicker steaks and broiling for steaks under 1 inch.
Step 5: Check the Temperature
Start checking early. Insert an instant read thermometer into the thickest part. Flank steak moves from perfect to overdone in about 2 minutes, so pull it 5 degrees below your target because carryover heat finishes the job during resting. If you want a full temperature breakdown by doneness level, my steak doneness guide covers every cut.
Flank Steak Temperature Chart: How Long to Cook Flank Steak in the Oven
Thickness changes timing more than anything else. Use these as starting points and trust your thermometer over the clock.
- 1 inch thick: bake 10 to 12 minutes at 425F, or broil 5 to 6 minutes per side.
- 1.25 inches thick: bake 12 to 15 minutes at 425F, or broil 6 to 7 minutes per side.
- 1.5 inches thick: bake 15 to 18 minutes at 425F, or broil 7 to 8 minutes per side.
Target internal temperatures:
- Rare: 125F (pull at 120F)
- Medium rare: 135F (pull at 130F)
- Medium: 145F (pull at 140F)
I recommend medium rare for flank steak. Past medium, the lean fibers tighten and the steak turns chewy no matter how well you slice it. For food safety reference, the FoodSafety.gov safe minimum internal temperatures chart lists 145F with a 3 minute rest as the safe minimum for whole beef cuts.
Rest the Steak, Then Slice Against the Grain
Transfer the steak to a cutting board and rest it for 10 minutes tented loosely with foil. Resting lets the juices redistribute instead of running out onto the board. Cutting early costs you a puddle of flavor.
Now the most important step. Look at the steak and find the direction the muscle fibers run. You will see long lines running along the length of the meat. Cut across those lines at a slight diagonal, slicing the steak into thin strips about 1/4 inch thick. Slicing against the grain shortens every fiber, so each bite chews easily instead of fighting your teeth. I have served flank steak sliced with the grain by accident, and the same steak went from tender to shoe leather. The grain is everything.
Broiler Method vs Bake Method: Which Is Better
Both methods produce excellent flank steak, but they suit different situations. Baking at 425F gives gentle, even heat and forgiving timing, which makes it the better choice for beginners and thicker steaks. Broiling gives intense direct heat that chars the surface fast, which builds better crust but demands attention. You cannot walk away from a broiler. I use the bake method on weeknights and the broiler when I want steakhouse style char for fajitas or tacos. Either way, the thermometer decides when it is done, not the timer.
How to Serve Oven Baked Flank Steak
Flank steak shines in sliced presentations. Layer the thin slices over a salad, pile them into warm tortillas for tacos, or serve them fanned out on a platter with chimichurri. My favorite weeknight plate pairs the slices with roasted potatoes and a simple arugula salad. The beefy flavor also stands up to bold sauces like horseradish cream or a garlicky aioli. Leftovers keep well for 3 to 4 days refrigerated and reheat gently. If you often reheat steak, my guide on grill timing by cut and thickness also covers carryover and rest principles that apply here.
Common Mistakes That Ruin Flank Steak in the Oven
Cooking It Past Medium
Flank steak has almost no intramuscular fat to keep it juicy. Every degree past 145F tightens the fibers and squeezes out moisture. Treat medium rare as your target and medium as your ceiling.
Skipping the Thermometer
Touch tests and timing guesses fail on lean cuts. A 10 dollar instant read thermometer removes all guesswork. Check the thickest part and pull early for carryover.
Slicing With the Grain
This ruins more flank steaks than overcooking. Always identify the grain direction first, then cut across it. If the grain shifts direction along the steak, rotate the piece and follow it.
Not Resting the Meat
Cutting into the steak straight from the oven spills the juices you worked to keep. Ten minutes of rest makes a visible difference in juiciness.
FAQ: How to Cook Flank Steak in the Oven
How long do you cook flank steak in the oven at 425F?
Bake flank steak at 425F for 12 to 15 minutes for a 1.25 inch thick steak, flipping once halfway. Start checking the internal temperature at 10 minutes and pull it 5 degrees below your target doneness.
Should you marinate flank steak before baking?
Yes. Marinate flank steak for 2 to 12 hours before baking. The marinade adds flavor and helps tenderize the lean surface. Pat the steak dry before it goes in the oven so it sears instead of steaming.
What temperature should flank steak be cooked to?
Cook flank steak to 135F for medium rare or 145F for medium. Medium rare gives the best texture. Pull it 5 degrees early and let carryover heat finish it during the 10 minute rest.
Can you cook flank steak in the oven without searing first?
Yes. A hot oven at 425F or a close broiler builds enough browning on its own when the surface is patted dry. Preheating the pan in the oven also gives the bottom a head start on searing.
Why is my oven baked flank steak tough?
Tough flank steak usually means one of three things: it cooked past medium, it was sliced with the grain instead of against it, or it did not rest before slicing. Fix those three and the same cut turns tender.
What is the easiest method for how to cook a flank steak in the oven?
Follow this guide from start to finish: marinate, temper, bake at 425F or broil, pull at your target temperature, rest for 10 minutes, and slice against the grain. That complete process is how to cook a flank steak in the oven for tender results every time.
Now you know how to cook a flank steak in the oven from start to finish. With a flavorful marinade, a hot oven, a reliable thermometer, and thin slices cut against the grain, this lean, affordable cut turns out tender every single time.