1
Preheat the oven to 400°F.
2
In a mixing bowl, combine the spinach, parmesan, bechamel, nutmeg, salt and pepper. Transfer to a baking dish and sprinkle with breadcrumbs and more parmesan. Bake for 12-15 minutes, until golden and bubbly on top.
3
In a small saucepan, melt the butter for the au poivre sauce over medium-low heat. Add the shallots and a pinch of salt and pepper. Sauté until softened and translucent. Add the sherry and bring to a boil.
4
Add the beef broth and soy sauce. Bring to a simmer for 15 minutes.
5
In a small bowl, combine the cornstarch with 1 tablespoon cold water to make a slurry. Stir into the sauce and bring to a boil.
6
Reduce the heat to low, add the cream and green peppercorns and simmer for 10 minutes. Adjust seasoning with salt and pepper.
7
Dry the steaks and coat with salt and pepper.
8
Heat the oil in a large skillet or a grill over high heat. Add the steaks and sear each side for 2 to 3 minutes, until dark brown. Transfer to a baking sheet and finish cooking in the oven to your desired doneness, 8 to 12 minutes. Rest for 5 minutes before slicing on the diagonal.
9
Divide the spinach gratin and steaks between plates to serve. Drizzle with sauce.