Pork Tenderloin Vitello Tonnato

Ingredients

• 1 pork tenderloin
• Kosher salt and freshly ground black pepper
• 1/2 cup extra-virgin olive oil, plus more for drizzling
• 1/2 cup plus 1 tablespoon vegetable oil, divided
• 1 whole egg
• 1/4 cup fresh juice from 2 lemons, divided
• 1 teaspoon Dijon mustard
• 1 teaspoon drained capers
• 2 anchovy fillets
• 1 can tuna in olive oil, drained
• Flat-leaf parsley leaves, thinly sliced celery and celery leaves, thinly sliced fennel bulb and fennel fronds, thinly sliced caper berries, and/or thinly sliced radish, for garnish

Directions

1. Heat the oven to 250 degrees F. Set the pork on a baking sheet with a rim, then season it well with salt and pepper. Add a drizzle of olive oil and use your hands to coat it lightly. Roast until an instant-read thermometer reads 140 degrees F, about 30 minutes.
2. Warm 1 tablespoon vegetable oil in a large skillet over high heat, just until it starts to smoke lightly. Add the pork and brown it on every side, about 5 minutes total. Move the pork to the refrigerator and let it chill for at least 1 hour and up to 8 hours.
3. While the pork chills, put the egg, 2 tablespoons lemon juice, mustard, capers, and anchovies into the bottom of an immersion blender cup. Pour the remaining 1/2 cup vegetable oil over them and let everything settle for 15 seconds. Set the immersion blender head down at the base of the cup and turn it on. Once the mayonnaise begins to come together, slowly angle and raise the blender until the oil is fully emulsified. Add the tuna and the remaining 2 tablespoons lemon juice, then blend until the sauce is smooth and completely combined.
4. Scrape the mayonnaise into a large mixing bowl. Slowly stream in 1/2 cup olive oil while whisking, until it emulsifies. Season with salt and pepper.
5. Cut the pork across the grain into very thin slices. Lay the slices on a large plate, spoon the tuna mayonnaise over the top, and spread it into an even layer. You can cover the pork tonnato with plastic and refrigerate it for up to 8 hours; the flavor gets better as it rests.
6. Just before serving, toss the garnish with a small drizzle of olive oil and salt. Arrange it over the top and serve right away.