Sprinkle both sides of the tenderloin steaks with 1 teaspoon salt and 1/2 teaspoon black pepper. Make sure to season them evenly for maximum flavor.

Place the seasoned steaks into a vacuum seal bag and seal them to remove all the air. Alternatively, use the water displacement method if you do not have a vacuum sealer. Heat a water bath to 125°F (52°C). Add the sealed beef to the water and let it cook sous vide for 3 hours. This low, slow cook ensures the steaks are evenly cooked and incredibly tender. I find that using the water displacement method is just as effective if you don't have special equipment.

While the steaks are cooking, make the creamy horseradish sauce. In a mixing bowl, combine the prepared horseradish, sour cream, mayonnaise, Worcestershire sauce, freshly squeezed lemon juice, 1 teaspoon salt, and 1/2 teaspoon black pepper. Stir everything together until smooth. I like to let the sauce sit in the refrigerator for at least 30 minutes—this lets the flavors meld beautifully.

Once the sous vide cooking is finished, carefully remove the steaks from the vacuum bag. Pat them completely dry with paper towels—removing moisture is key to getting a good sear later.

Heat a cast iron skillet over high heat until it starts to smoke. Add the avocado oil, then place the dried steaks in the pan. Sear each side for 45-60 seconds, just until a brown crust forms. Avoid cooking the steaks any longer, as you want to keep their perfectly tender interior. I always recommend pressing the steaks gently into the pan to maximize that savory crust.

Arrange the beautifully seared steaks on plates and top with a generous dollop of the horseradish cream sauce from Step 3. Sprinkle chopped chives over the top for a final burst of color and freshness. Serve immediately while everything is hot and flavorful.