Name: Filet of Beef with Mustard Horseradish Sauce
Cook time: P0Y0M0DT0H15M0.000S
Total time: P0Y0M0DT1H0M0.000S
Yield: 8 to 10 servings
Ingredients: 1 whole filet of beef (4 to 5 pounds), trimmed and tied; 2 tablespoons unsalted butter at room temperature; 1 tablespoon kosher salt; 1 tablespoon coarsely ground black pepper; Mustard Horseradish Sauce (recipe follows); Fresh parsley, for serving; 1 1/2 cups good mayonnaise; 1/3 cup sour cream; 3 tablespoons Dijon mustard; 1 1/2 tablespoons whole-grain mustard; 1 tablespoon prepared horseradish; 1/4 teaspoon kosher salt

Directions

Preheat the oven to 500 degrees F.
Place the beef on a baking sheet and pat the outside dry with a paper towel. Spread the butter on with your hands. Sprinkle evenly with the salt and pepper. Roast in the oven for exactly 22 minutes for rare and 25 minutes for medium rare.
Remove the beef from the oven, cover it tightly with aluminum foil, and allow it to rest at room temperature for 20 minutes. Remove the strings and slice the filet thick, 1/2-inch thick per slice. Transfer to a serving platter. Garnish with parsley. Serve warm, at room temperature, or cold with Mustard Horseradish Sauce on the side.