Ocean Steak Recipe

Prepare steaks

Pat the swordfish or tuna steaks dry with paper towels. Trim any sinew if needed. Season both sides evenly with 1 teaspoon kosher salt and 1 teaspoon freshly ground black pepper.

Heat pan

Place a heavy skillet (cast-iron preferred) over medium-high heat. Add 2 tablespoons olive oil and heat until shimmering but not smoking (about 2 minutes).

Sear steaks

Carefully place the steaks in the hot pan. Sear without moving for 2.5–3 minutes to develop a golden crust. Flip and sear the other side for 2–3 minutes for medium doneness (internal temperature ~125–130°F / 52–54°C). For well-done, cook an additional 1–2 minutes per side. Remove steaks to a warm plate and tent loosely with foil to rest while you finish the sauce and add the herb butter.

Make the butter

While the pan is heating or while steaks rest, combine 4 tablespoons softened unsalted butter, 2 tablespoons finely chopped parsley, 1 tablespoon finely chopped dill, 1 teaspoon lemon zest, 1 tablespoon chopped capers, 1 tablespoon lemon juice, and 1 teaspoon finely ground seaweed flakes (if using) in a small bowl. Season with 1/4 teaspoon salt and 1/4 teaspoon black pepper. Mix until smooth and homogeneous.

Chill or shape (optional)

If desired, shape the compound butter into a log on plastic wrap and chill for 15–30 minutes to firm. Alternatively, keep spreadable at room temperature and divide into two portions to top each steak just before serving.

Deglaze the pan

After removing steaks, return the skillet to medium heat. Add the minced shallot and sauté for 30–45 seconds until fragrant. Pour in 1/4 cup dry white wine or fish stock to deglaze, scraping up any browned bits from the bottom with a wooden spoon. Let the liquid reduce by about half (1–2 minutes).

Finish the sauce

Reduce heat to low. Whisk or swirl in 2 tablespoons cold cubed butter, one piece at a time, allowing each to emulsify into the sauce to create a glossy finish. Adjust seasoning with a pinch of salt and a grind of black pepper. Remove from heat.

Top steaks and plate

Place each rested steak on a plate. Spoon a little pan sauce over each. Top each steak with a generous slice or dollop (about half) of the ocean herb butter so it begins to melt over the warm fish. Garnish with a few microgreens or watercress and serve lemon wedges on the side.