Seared Beef Tenderloin with Mustard-Horseradish Sauce

Preparation

1. Step 1

   Tie beef with kitchen string to hold shape. Sprinkle with salt and pepper. Heat heavy large skillet over medium-high heat. Rub 1 tablespoon oil over beef. Add beef to skillet. Sear until brown on all sides and cooked to desired doneness, about 20 minutes for medium-rare. Transfer beef to plate. Freeze until almost frozen solid, about 3 hours. Remove string. Using large sharp knife, cut beef crosswise into very thin slices. (Can be prepared 8 hours ahead. Arrange slices between sheets of waxed paper on baking sheet. Cover tightly and refrigerate.)

   Step 2

   Cover large platter with watercress. Arrange beef slices atop watercress. Drizzle with 2 1/2 tablespoons oil. Sprinkle with capers and Parmesan cheese. Drizzle with lemon juice. Sprinkle with pepper. Serve with baguette slices and sauce.