Grilled Pork Tenderloin with Salsa Verde

• 1 pork tenderloin (about 1 lb.)
• 1/3 cup plus 1 Tbs. extra-virgin olive oil
• 1/4 tsp. dried oregano
• Kosher salt and freshly ground black pepper
• 1 cup packed fresh flat-leaf parsley leaves, washed and spun dry
• 1/4 cup shelled walnuts
• 1 small clove garlic
• 2 Tbs. capers, drained
• 1 Tbs. fresh lemon juice
• 1 tsp. Dijon mustard
• 1 oil-packed anchovy fillet, rinsed and patted dry

Heat a gas grill to medium or prepare a medium-hot charcoal fire. Trim the pork of any excess fat and silverskin (see How to trim a tenderloin) . Rub the pork with 1 Tbs. of the oil, the oregano, 1/2 tsp. salt, and 1/4 tsp. pepper. Set the pork on the hottest part of the grill and close the lid. Grill, covered, turning once, until an instant-read thermometer inserted into the center of the pork registers 140° to 145°F, about 15 to 20 minutes. Transfer the pork to a clean cutting board and let rest for 5 minutes.

While the pork is on the grill, combine the remaining 1/3 cup oil, the parsley, walnuts, garlic, capers, lemon juice, mustard, and anchovy in a blender. Pulse the mixture until it forms a coarse paste, about five or six pulses. (This salsa verde may be made a day ahead, covered, and refrigerated. Bring it to room temperature before serving.)

Slice the pork thinly and serve with the salsa verde spooned over it.