Three Mustards Flat Iron Steak

Grilled Three Mustards Flat Iron Steak is an excellent way to prepare one of the most tender cuts of beef.  Flat Iron Steak is cut from the top blade in prime shoulder of the steer; butchered to remove the connective tissue, it is well-marbled, and extremely tender and flavorful and great for grilling.  When flat-iron steak meets our tasty marinade made with three different types of mustard: dry mustard powder, Dijon mustard and the whole grain Old Style/Country mustard, it is a match made in heaven, especially when the balance of the marinade is combined with heavy cream to make a delicious sauce.  Make Grilled Three Mustards Flat Iron Steak the star of your next dinner, serve it with Simple Sauteed Snow Peas and a crusty loaf of bread, accompanied by a robust Old Vine Zinfandel or Cabernet Sauvignon.

Three Mustards Flat Iron Steak

Prep Time: 30 minutes plus 24 hours marinating time, Grilling and Resting Time: 25 minutes.  Serves 2 to 4.

 Support Cook and Eat at Home. Purchase a PDF of the Three Mustards Flat Iron Steak recipe for $1.00. 

Ingredients:

  • ½ tsp coarse Sea Salt
  • 1 Tb Brown Sugar
  • 1 tsp ground Black Pepper
  • 1 Tb Dry Mustard powder
  • 1 Tb granulated Onion
  • 1 Tb granulated Garlic
  • 1 Tb Dijon Mustard
  • 1 Tb Old Style/Country Mustard
  • 4 Tbs Red Wine Vinegar
  • 1 cup dry Red Wine
  • 2 Tbs Extra Virgin Olive Oil
  • 1 ½ to 2 lbs. Flat Iron Steak
  • 4 Tbs Heavy Cream

Three Mustards Flat Iron Steak

Preparation:

  1. Combine the sea salt, brown sugar, black pepper, dry mustard powder, granulated onion and garlic, Dijon mustard, old-style/country mustard, red wine vinegar, red wine, and extra virgin olive oil in a bowl and whisk together to emulsify the marinade.
  2. Place the flat iron steak in a sealable plastic bag, pour the marinade into the bag, squeeze the air out of the bag, seal and refrigerate; marinate the flat iron steak for 24 hours.
  3. 1 hour prior to grilling, remove the marinated flat iron steak in its bag from the refrigerator.
  4. Bring the grill to a high heat
  5. Grill the meat directly over a high heat for 7 ½ minutes per side, basting with the marinade while grilling.
  6. Using a meat thermometer, measure the internal temperature of the flat iron steak; it should be around 130 F for medium rare or 140 F for medium, we do not recommend anything beyond medium.
  7. Remove the flat iron steak from the grill to a cutting board, tent it with aluminum foil and allow to rest for 10 minutes.
  8. While the flat iron steak is resting, bring the balance of the marinade to a boil in a saucepan, add the heavy cream, stir and reduce the sauce by half.
  9. Remove the foil, slice the Three Mustards Flat Iron Steak on the bias and serve, napped with the sauce.

Three Mustards Flat Iron Steak