Best Way Of Cooking Flat Iron Steak in Oven

Last Updated on by SteakEat

Today I show the best way of cooking flat iron steak in oven.

Flat iron steak, sometimes sold as butler’s steak, is a cut that comes from the shoulder of a beef cow and is cut with the grain of the muscle.

It means that it is less tender than steak cuts from the loin part of the animal, so we’ll need to look after that.

Nevertheless, it is prized for its deep flavor and with careful preparation and cooking makes a delicious meal.

It can be cooked using a variety of techniques and one of the more unusual ones is to cook it in the oven, without using the broiler.

What follows are some simple techniques that help learn the basics of how to bake flat iron steak in an oven.

Before we begin…I wanted to share these 3 secrets behind every perfect steak – get them.

All right, let’s do it!


Preparing a Good Marinade

Even if you a get a top quality grass-fed flat iron steak (I recommend this one), you MUST use a marinade with this cut because, yeah…it’s pretty tough.

US-born Grass-Fed Flat Iron Steak That I recommend (click to learn more)

All good flat iron steak recipes in oven start with an excellent marinade. You’ll need one that adds flavor but also helps to tenderize the meat.

Flat iron steaks have a regular shape because they are cut with the grain of the muscle and this is why a marinade is a good idea.

Start your marinade with a combination of oil and acid.

Acids such as fruit juices or wine vinegars begin the important process of breaking down the fiber of the flat iron steak whilst oils, such as olive oil, will help flavor permeate into the meat.

Flavor can be provided from your own choice of herbs and spices. Rosemary is the one you can begin with.


To Create a Perfect Marinade For Flat Iron Steak You Need

  • Pineapple juice
  • Extra virgin olive oil
  • Fresh rosemary
  • Garlic
  • Freshly ground black pepper

And here are the steps:

  1. Pour enough pineapple juice to half cover your steaks into a glass dish (don’t use metal ones as they may react with the acids in the pineapple juice)
  2. Add extra virgin olive oil, in the same quantities so that you now have enough liquid to cover your steaks
  3. Take three large sprigs of fresh rosemary and bruise with the back of a knife and add to the dish
  4. Slice two cloves of garlic and add them
  5. Complete the marinade with a good twist of freshly ground black pepper – don’t add salt at this stage of the process and it will encourage the steak to give up its precious juices

Put the steaks into the dish and cover tightly. Alternatively use a food-safe plastic bag that you can reseal. It helps to avoid all the mess.

Leave the steaks in the refrigerator for two to three hours.

Don‘t leave them longer as the marinade will break down the texture of the steak too much and it will become mushy.

Other fruit juices such as papaya or citrus fruits are also excellent bases for marinades to use when cooking a tender flat iron steak in the oven.

Buttermilk is also an excellent tenderizer as it is rich in natural enzymes that help break down protein molecules naturally.


Cooking a Flat Iron Steak in the Oven

Oven temperature for flat iron stakes is critical.

Too low and the steak will take ages to get ready, despite the best efforts of your marinade.

Too high, it will cook too quickly and the steak will dry out and become hard to chew.

The ideal temperature to cook a tender flat iron steak in the oven is 350 degrees Fahrenheit.


To Cook Flat Iron Steak in Convection Oven

  1. Take your steaks out of the refrigerator 40 minutes before you plan to start cooking, this will allow the meat to come to room temperature and ensure even cooking.
  2. Preheat the oven to 350 degrees F.
  3. Place the beef on a rack in the roasting pan and put it into the oven.
  4. Bake the steak, 10 minutes for rare, 12 minutes for medium-rare, 15 minutes for medium and 20 minutes for well done.
  5. Remove the steaks and put aside in a warm place to rest.
  6. While the meat is resting, make a sauce to dress the streak using the juices in the pan and by adding some marinade to the pan to deglaze it.
  7. Heat the oven pan on the stove top and reduce the marinade until it is thick and tasty. Make sure to get marinade to boiling temperature, so that you can make sure all the possible bacteria that cause food-borne illnesses are destroyed.

Season your steak with salt and pepper after it has rested to maintain maximum juiciness. Serve it with a fresh green salad and some French fries for a perfect meal and complete the dining experience with a glass or two of your favorite Shiraz wine.




When you take your steak out, you will notice that it’s not browned and doesn’t have a tasty crust. To fix that, heat up the skillet on the stove top and sear the steak for around 40 seconds on each side.
You can check out the SteakEat Method for more guidance on using the stove.


P.S. The 3 secrets behind a juicy, tender steak. Don’t miss them!

Ready To Enjoy That Juicy Tender Steak Every Single Time?

1. Get the Best Steak. Cooking steak to perfection is only 50% of success!
The other 50% come from great quality steak and I recommend you get those from here. Especially their grass-fed beef (they also have poultry, pork and loads of game!)