How to Make It
Heat a large skillet. Add the spinach by the handful and cook over moderately high heat, tossing with tongs, until wilted. Transfer to a colander, rinse under cold running water and gently squeeze out the excess water.
Heat 2 tablespoons of the olive oil in a large skillet. Add the bacon and shallot and cook over moderate heat, stirring occasionally, until the bacon is browned and the shallot is softened, about 4 minutes. Add the chicken stock and mushrooms and simmer over moderate heat until the mushrooms soften, about 7 minutes. Add the tomatoes and soy sauce and cook over high heat until the liquid is reduced by one-third, about 4 minutes.
In a large nonstick skillet, heat 1/2 tablespoon of the olive oil until almost smoking. Season the monkfish with salt and white pepper and add 8 of the medallions to the skillet. Cook over moderately high heat until nicely browned on the bottom, about 3 minutes. Turn the medallions and cook until just opaque throughout, about 1 minute. Transfer the medallions to a warm platter, cover with foil and repeat with the remaining monkfish and oil. Wipe out the skillet and add the cooked spinach. Cook over high heat, stirring, until warmed through. Season with salt and white pepper.
Bring the mushroom sauce to a simmer. Add the chives and tarragon and whisk in the butter, 1 tablespoon at a time. Season with salt and white pepper. Mound the spinach in the center of 4 warm plates; top each mound with 4 monkfish medallions. Spoon the sauce over the fish, sprinkle with the nori strips and serve.