Ingredients
1 2 1/2-pound beef tenderloin, tied with kitchen string
2 tablespoons extra-virgin olive oil, plus more for rubbing
Coarse salt and freshly ground pepper
1 leek, white and pale-green parts only, washed well and chopped (about 1 cup)
1/4 cup packed fresh flat-leaf parsley leaves, plus sprigs for garnish
1 ounce Parmesan, finely grated (1/3 cup)
1/2 cup panko breadcrumbs
Preparation
Let beef tenderloin stand at room temperature 1 hour. Preheat oven to 425 degrees. Pat beef dry with paper towels; transfer to a parchment-lined rimmed baking sheet. Rub beef with oil and season all over with 1 tablespoon coarse salt and 1/4 teaspoon pepper. Roast 20 minutes.
Meanwhile, pulse leek, parsley, and Parmesan in a food processor until finely chopped. Add oil and pulse until combined. Transfer to a bowl and stir in panko. Season with salt and pepper.
Remove beef from oven; cut and remove string. Gently pack leek mixture on top and sides with a rubber spatula. (Don’t worry if some falls off; it will become crisp and golden.) Return tenderloin to oven and continue to roast until crust is golden brown and a thermometer inserted into center reaches 130 degrees (for medium-rare), 15 to 20 minutes. Let rest 15 minutes before slicing. To serve, place on a serving platter and garnish with parsley sprigs.