TIP: You can replace the horseradish in the sour cream mixture with 3 tablespoons drained and finely chopped pickled jalapeños. You’ll find this version of the recipe in Magnolia Table Cookbook.
1/2 cup soy sauce
1/2 cup Worcestershire sauce
1/2 cup brine from pickled jalapeños
One 3 to 3 1/2 pounds center-cut beef tenderloin, trimmed and tied
2 teaspoons salt
1 teaspoon black pepper
1 teaspoon granulated onion
1 teaspoon red pepper flake
1 teaspoon granulated garlic
2 tablespoons salted butter, at room temperature
Horseradish Sour Cream
1 1/2 cups sour cream
1/4 to 1/2 cup horseradish (see Cook’s Note)
2 tablespoons Dijon mustard
2 tablespoons minced chives
Kosher salt and freshly ground black pepper
Marinate the beef tenderloin: pour the soy sauce, Worcestershire sauce, jalapeño brine, salt, pepper, granulated garlic, granulated onion, and red pepper flakes.
Remove the tenderloin from the bag and discard the marinade. Blot the roast dry with paper towels and let sit at room temperature for an hour.
Meanwhile, make the horseradish sour cream: In a small bowl, stir together the sour cream, horseradish, Dijon mustard and chives. Season with salt and pepper, to taste.
Position a rack in the middle of the oven and preheat the oven to 500°F. Line a baking sheet with foil.
Place the tenderloin on the lined baking sheet and spread the 2 tablespoons of butter over the top.
Roast for 9 to 11 minutes (3 minutes per pound). Turn off the oven. Leave the roast in the oven for 20 minutes for medium-rare (125°F on an instant-read thermometer) or 25 minutes for medium (130°F on an instant-read thermometer). Do not open the oven door.
Transfer to a cutting board and let rest for 15 minutes before slicing.
Tightly wrap leftover beef in plastic and store in the refrigerator for up to 3 days. Leftover cooked beef makes delicious cold sandwiches. Store leftover horseradish cream in a covered container in the refrigerator for up to 3 days.