After the beef finishes cooking, let it stand at room temperature for at least 10 minutes before carving. Keep in mind it will continue to cook after it has been removed from the oven.
Recipe information
Yield
serves 4
Ingredients
Preparation
Step 1
Preheat the oven to 375°F. Sprinkle the beef with 1/2 teaspoon salt, and season with pepper. Heat the oil in a large ovenproof sauté pan over high heat until hot but not smoking. Add the beef; brown on all sides, about 5 minutes total. Remove the pan from heat.
Step 2
Place the onion halves in the pan, cut sides down. Transfer the pan to the oven. Cook the beef and onions until an instant-read thermometer inserted into the center of the beef registers 140°F (for medium-rare), 35 to 40 minutes. Transfer the beef to a wire rack set over a rimmed baking sheet, and let stand 10 minutes before carving. Reserve the onions.
Step 3
Stir together the sour cream, horseradish, lemon juice, 1/4 teaspoon salt, and pepper to taste in a small bowl. Serve the beef with the horseradish sauce and roasted onions.
