- FOR THE TENDERLOIN:
- 2 tablespoons olive oil
- 1 tablespoon Creole Seasoning
- One 2-pound beef tenderloin, trimmed of fat
- FOR THE HORSERADISH SPREAD:
- 3 tablespoons Mayonnaise 
- 1 tablespoon prepared horseradish
- 1/8 teaspoon salt
- 1/8 teaspoon cracked black peppercorns
- TO ASSEMBLE:
- 2 cups baby arugula, rinsed and patted dry
- 1 tablespoon extra-virgin olive oil
- 1/4 teaspoon salt
- 1/8 teaspoon freshly ground black pepper
- 1 loaf French bread (about 15 inches long), cut crosswise into 1/4-inch-thick slices and lightly toasted
- 1/2 pound Parmigiano-Reggiano cheese, shaved with a vegetable peeler
- Preheat the oven to 350?F.
- In a small mixing bowl, mix together the olive oil and Creole seasoning. Spread this evenly over the tenderloin. Heat a large ovenproof skillet over medium-high heat, then sear the tenderloin for 5 minutes on each side in the skillet. Transfer the skillet to the oven and roast for 25 minutes for medium-rare. Remove from the oven and let rest for 30 minutes.
- Cut the tenderloin into thin slices.
- In a small mixing bowl, combine the mayonnaise, horseradish, salt, and black pepper and whisk to mix. Cover and refrigerate until ready to use.
- In a medium-size mixing bowl, toss the arugula with the olive oil, salt, and pepper.
- Spread about 1/2 teaspoon of the horseradish mixture on each slice of toast. Top with a slice of beef and a few cheese shavings, then finish with a little of the arugula. Top each sandwich with a slice of toast. Pass on a platter to serve.