ROAST FILLET OF BEEF WITH MUSHROOM SAUCE

1 fillet of beef (2 pounds), silver skin removed
Kosher salt and freshly ground black pepper
1 tablespoon olive oil, plus more for pan
1 tablespoon plus 1 teaspoon unsalted butter, divided use
4 ounces cremini mushrooms, trimmed, thickly sliced
4 ounces oyster mushrooms, trimmed, thickly sliced
4 ounces shiitake mushrooms, stems removed and thickly sliced
1 medium shallot, minced
1/2 cup Madeira
1 cup low-sodium beef stock

Preheat the oven to 375 degrees F.

Season the beef with salt and pepper on all sides.

Heat a large cast-iron skillet until hot. Coat lightly with oil, and sear the meat on all sides until well-browned all over, 8 to 10 minutes.

Transfer skillet to the oven and roast until the meat reaches an internal temperature of 130 degrees, for medium-rare, about 25 minutes. Transfer to a cutting board and let the meat rest 10 minutes before slicing.

Meanwhile, saute mushrooms: Heat 1 teaspoon oil and 1 teaspoon of butter over high heat in a frying pan large enough for the mushrooms without crowding.

Add the cremini mushrooms and season with a pinch of salt and pepper. Saute until golden brown, tossing frequently, 5 to 7 minutes. Transfer to a plate and set aside.

Add 1 teaspoon oil and 1 teaspoon butter to the pan and saute the oyster mushrooms. Add to the creminis and set aside.

Repeat process with the shiitake mushrooms and set aside.

Add the remaining 1 teaspoon butter and the minced shallot to the pan. Saute over medium heat, stirring frequently, until the shallot has softened but hasn't begun to brown, about 2 minutes.

Add the Madeira and cook until it has reduced to a glaze, about 3 minutes.

Add the beef stock and cook until slightly thickened, about 5 minutes. Season with salt and pepper to taste.

TO SERVE:
Just before serving, reheat all mushrooms in a hot frying pan for a few seconds. Slice the meat into medallions and arrange on a platter. Arrange mushrooms around roast. Pour sauce over the meat, or serve on the side in a warm sauceboat.

Servings: 4 to 6
Adapted from source: Recipes: A Collection for the Modern Cook, Susan Spungen