Ingredients

Coarse salt or sea salt

2 lobsters (each about 1 1/4 pounds)

1/4 cup plus 1 tablespoon low-sodium soy sauce

1 tablespoon cornstarch

1 tablespoon water

1/2 cup homemade or low-sodium store-bought chicken stock

1/3 cup oyster sauce

3 tablespoons mirin

3 tablespoons fresh lemon juice

2 tablespoons coarsely chopped fresh cilantro, plus sprigs for garnish

1/2 teaspoon red-pepper flakes

4 beef tenderloin steaks (each about 5 ounces and 1 1/2 inches thick), tied

Freshly ground pepper, to taste

3 tablespoons peanut oil

8 scallions, white and pale-green parts only, cut into 2-inch pieces

16 thin slices peeled fresh ginger (about 1 1/2 inches in diameter)

8 garlic scapes (optional)

Steamed jasmine rice, for serving (optional)

Preparation

Prepare an ice-water bath. Fill a large stockpot 3/4 full with cold water. Bring to a boil. Add 1/4 cup salt. Plunge lobsters head first into water. Return to a boil, and cook 10 minutes. Using tongs, transfer lobsters to ice-water bath, and let cool 5 minutes. Place lobsters on a cutting board. Working with one lobster at a time, twist tail from joint where it meets body. Cut tail in half down center. Twist claws from body; discard body. Separate claws from knuckles. Crack knuckles, and remove meat. Grasp “thumb” of claw, and bend it back to snap it off. Crack claws, and remove meat.

Whisk 1/4 cup soy sauce, the cornstarch, and water in a bowl. Add lobster pieces, and toss; set aside to marinate.

Combine stock, remaining tablespoon soy sauce, the oyster sauce, mirin, lemon juice, chopped cilantro, and red-pepper flakes in a bowl.

Season beef on all sides with salt and pepper. Heat oil in a large skillet over medium-high heat. Add beef, leaving about 1 inch between each steak. Brown on all sides, about 8 minutes total. Add scallions, ginger, and garlic scapes if using. Reduce heat to medium. Cook, stirring scallions, ginger, and garlic scapes occasionally, until an instant-read thermometer inserted into beef registers 125 degrees for medium-rare, 4 to 6 minutes. Transfer steaks to a platter. Remove strings. Cover with parchment paper and then foil to keep warm.

Reduce heat to medium-low. Using a slotted spoon, add lobster pieces to sauce in skillet (reserve marinade). Cook, tossing gently, until warm, about 4 minutes. Transfer lobster to plate with beef.

Add oyster-sauce mixture and reserved marinade to sauce in skillet, and raise heat to high. Simmer, stirring occasionally, until sauce has thickened slightly, 1 to 2 minutes. Arrange beef and lobster on 4 plates. Pour sauce over top. Garnish with cilantro sprigs. Serve with rice if desired.