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There is something special about working with high-quality beef, and American Wagyu is truly in a league of its own. Its incredible marbling translates directly to buttery flavor, making it the perfect candidate for a high-heat sear on the Big Green Egg. For this cook, I chose the Flat Iron steak. Cut from the shoulder, this steak is remarkably tender and exceptionally flavorful, making it easy to create a restaurant-quality meal at home.
In this post, I will walk you through a savory Korean-style marinade that complements the rich beef without overpowering it, and share the techniques needed to nail a perfect medium-rare crust. So, sit back, grab a glass of Cabernet Sauvignon, and enjoy this recipe for How to Grill Korean Wagyu Flat Iron Steak on the Big Green Egg.
Table of Contents
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What is Wagyu Beef?
The cornerstone of this recipe is American Wagyu beef. While “Wagyu” literally translates to “Japanese cow,” American Wagyu is produced by breeding Japanese cattle with high-quality American herds.
This genetic combination results in intense marbling—fine specks of intramuscular fat that melt during cooking, creating unmatched tenderness and flavor.
Note: While all Kobe beef is Wagyu, not all Wagyu is Kobe. True Kobe beef comes exclusively from the Hyōgo Prefecture in Japan and is world-renowned for its strict quality standards.
For this cook, I am using a Flat Iron Steak, which is cut from the shoulder. It is often referred to as the second most tender steak after the tenderloin, but with far more robust flavor.
Korean-Style Marinade
To complement the rich marbling of the Wagyu, we need a marinade that balances salty, sweet, and aromatic notes.
Ingredients
- Soy Sauce
- Rice Vinegar
- Korean Rice Wine (or Sake)
- Hoisin Sauce
- Fresh Garlic (cloves)
- Fresh Ginger
Instructions
- Prep Aromatics: Using a mortar and pestle, mash the garlic and ginger together into a paste to maximize flavor extraction.
- Combine: Mix the paste with the soy sauce, rice vinegar, rice wine, and hoisin sauce until well blended.
- Marinate: Place the Wagyu flat iron steak in a sealable plastic bag, pour the marinade over it, and refrigerate for 2 to 4 hours to allow the flavors to penetrate the meat.
Grilling the Wagyu Flat Iron Steak
After a few hours in the marinade, remove the steak from the refrigerator and let it come to room temperature while you prep the grill. This ensures even cooking from edge to edge.
Stabilize your Big Green Egg for direct grilling at a scorching 600°F. The high heat is necessary to sear the outside quickly while keeping the interior tender. Place the steak directly on the hot grate and cook for 5 minutes per side.
Once seared, pull the steak off the heat and let it rest for at least 10 minutes before slicing. This allows the juices to redistribute throughout the meat, ensuring every bite is perfectly cooked and incredibly flavorful.
Serving Suggestion & The Perfect Pairing
To truly honor the quality of the American Wagyu, I sliced the steak against the grain into thin strips to showcase the intense marbling and tender texture.
For a simple side, I served it over steamed white rice, which pairs perfectly with the savory Korean glaze. While the steak was resting, I took advantage of the hot grill to cook some shrimp, covering them in the same rich Korean BBQ sauce I made for my ribs last week to create a surf-and-turf feast.
Wine Pairing Tip: The deep, savory flavors of the marinade and the richness of the beef require a wine with enough body and tannin to cut through the fat. A robust Cabernet Sauvignon is the perfect choice, balancing the umami notes of the Hoisin and soy while complementing the smoky char from the grill.
Final Assembly and Serving
After resting, I sliced the steak thinly against the grain to maximize tenderness and showcase the incredible marbling. To complete this Korean-inspired feast, I served the Wagyu alongside savory Kimchi Fried Rice and the Korean BBQ Shrimp I grilled earlier. The vibrant spice of the kimchi fried rice perfectly cuts through the richness of the Wagyu, while the sweet and savory shrimp adds another layer of flavor. It is a true surf-and-turf experience that is absolutely delicious!
How to Grill Korean Wagyu Flat Iron Steak on the Big Green Egg
Ingredients
- 2 lbs Wagyu Flat Iron Steak
- 1/2 c soy
- 1/4 c rice vinegar
- 1/4 c Korean rice wine
- 1/4 c Hoisin sauce
- 2 cloves garlic, minced
- 1 Tbls ginger, minced
Instructions
- Combine the soy, vinegar, rice wine, Hoisin, garlic, and ginger
- Put the flat iron steak in a large Ziploc bag and marinate for 2 to 3 hours
- Take the steak out of the marinade and allow to come up to room temperature
- Light your Big Green Egg and preheat to 600°
- Cook the steak over direct heat for 5 minutes per side or until the internal temp measures 125° for medium rare
- Pull the steak off the grill and let rest for 10 minutes
- Slice against the grain and serve
Nutrition information is automatically calculated, so should only be used as an approximation.
