Grilled Flat Iron Steak with Mustard Red Onion Marinade

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Recipe intro

This recipe for grilled flat iron steak with mustard red onion marinade is a mouthwatering combination of flavors and textures. The steak is marinated in a tangy blend of mustard and red onions, which adds a delicious depth of flavor to the meat. Grilling the steak gives it a smoky char and locks in the juiciness, resulting in a tender and flavorful dish. Perfect for a summer barbecue or a special dinner, this recipe is sure to impress your guests.

Keywords: grilled, flat iron steak, mustard, red onion marinade, barbecue.

Grilled flat iron steak with mustard red onion marinade recipe details

Grilled flat iron steak with mustard red onion marinade recipe, recipe Rating: 4.8
Number of votes:136

This tender steak gets the old one-two combo–marinating in mustard, then getting a spice rub. Hey, the more flavor the better. Inspired by madcow’s “Mean Mr. Mustard (Steak).”
Ready in: 1 hour 30 mins

Ingredients

Makes: 1 steak

• 1/2 cup stone-ground mustard
• 1 cup diced red onions
• 1 flat iron steak (or more)
• 1 tablespoon coarse salt
• 1 tablespoon freshly ground black pepper
• 1 tablespoon garlic powder
• 1/2 tablespoon ground coriander
• 1/2 tablespoon paprika

Preparation method

Prep: 15 mins | Cook: 15 mins | Extra time: 1 hour, marinating

1. Combine mustard and red onions. Coat both sides of steak with the sauce, reserving a small amount. Place in shallow dish, cover with plastic wrap and refrigerate for 1 hour to marinate.
2. Combine salt, pepper, garlic powder, coriander, and paprika to create a spice rub. Season steak liberally with mixture, about 1 teaspoon per side.
3. Heat your gas or charcoal grill to high (Here’s how to tell if it’s high: Hold your hand about four inches above the cooking surface. After 2 to 3 seconds, the heat will force you to pull your hand away.)
4. Oil the grill grate, using an oiled rag.
5. Brush excess onion/mustard mixture off steaks and place meat on the grill. Use these cooking times to cook your steak to medium: 2 to 3 minutes per side for a 1/2-inch thick steak, 4 to 6 minutes per side for a 1-inch thick steak, 6 to 9 minutes per side for a 1 1/2 to 2-inch thick steak.
6. Take the steak off the grill. Let it rest 2 to 3 minutes to allow the juices to reabsorb into the steak. Serve.Note

Recipe makes 1 1/2 cups marinade, enough for 3 pounds of steak, and 1/4 cup spice rub.