Ingredients
Beef Tenderloin
- 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
 
Directions
- 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.