Shio Koji London Broil with Blistered Shishito Peppers (A Wagyu Technique Recipe)

Where Technique Meets Wagyu: Shio Koji London Broil

Shio Koji London Broil

An Unexpected Expression of Wagyu

Recipes & Cooking Tips

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Recipes & Cooking Tips

Shio Koji London Broil

An Unexpected Expression of Wagyu

At Prime Wagyu Farm, we believe exceptional beef is not limited to the obvious cuts.

While ribeyes and tenderloins often steal the spotlight, there is something deeply satisfying about transforming a leaner cut into something extraordinary. This Shio Koji London Broil is a celebration of technique, patience, and the quiet depth of Full-Blood Wagyu.

London Broil refers not to a specific cut, but to a method. Traditionally used for leaner muscles such as top round, it relies on three essential steps: a purposeful marinade, high-heat searing, and careful slicing against the grain. When executed properly, the result is tender, deeply flavorful beef with a beautiful crust and elegant texture.

For this preparation, we use shio koji, a traditional Japanese fermented rice paste that embodies both science and simplicity. Its natural enzymes break down proteins and carbohydrates, gently tenderizing the meat while enhancing savory depth. The result is subtle sweetness, amplified umami, and a surface that sears beautifully under high heat.

When paired with blistered shishito peppers finished in sesame oil and sea salt, this dish becomes balanced and refined. The richness of Wagyu meets bright, lightly smoky peppers in a way that feels both rustic and sophisticated.

This recipe is an invitation to cook with intention. It reminds us that extraordinary meals are not only about premium cuts, but about understanding the craft.

Prep Time: 1–3 hours

Cook Time: 25–30 minutes

Serves 4–6 people

Ingredients

For the Marinade

2 lb Prime Wagyu Farm Top Round
3.2 oz shio koji
Flaked sea salt, to taste
1 tbsp cooking oil

Optional Dipping Sauce

Soy sauce
Wasabi

For the Shishito Peppers

2 lb sweet shishito peppers
1 tsp toasted white sesame seeds
2 tbsp Wagyu Beef Tallow
1 tbsp sesame oil
Pinch of flaked sea salt

Wagyu Top Round (London Broil)

$50.00

Wagyu Beef Tallow

$38.00

Directions

Marinating

Place the shio koji and top round in a resealable bag. Remove excess air and ensure the marinade fully coats the meat.
Refrigerate for at least 30 minutes, ideally 1–3 hours. Longer marination deepens flavor and tenderness.
Remove the steak from the marinade and pat completely dry. Excess marinade may burn during broiling.
Allow the steak to come to room temperature before cooking to encourage an even sear.

Cooking

Preheat the broiler on high for 10 minutes.
Season the steak lightly with flaked sea salt and drizzle with cooking oil.
Place on a sheet pan fitted with a roasting rack. Position about 4–5 inches from the broiler.
Broil 5–6 minutes per side for medium rare, or 6–7 minutes per side for medium. Avoid cooking beyond medium to preserve tenderness.
Remove and rest for 10 minutes.

Preparing the Shishito Peppers

Heat a large sauté pan or wok over medium heat.
Add 2 tablespoons Wagyu Beef Tallow.
Working in two batches, blister the peppers for 1–2 minutes per batch until softened and lightly charred.
Transfer to a bowl and toss with sesame oil, toasted sesame seeds, and a pinch of flaked sea salt.

To Serve

Slice the rested London Broil very thinly, approximately 1/8 inch thick, against the grain.
Plate alongside blistered shishito peppers.
Serve with soy sauce and wasabi if desired.

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