- 1 (6- to 6 1/2-pound) whole beef tenderloin, trimmed of fat, silverskin, and the chain (see Cooks' Notes); or a 5- to 5 1/2-pound well-trimmed tenderloin roast
- 4 ounces diced pancetta
- 2 pounds grape tomatoes
- Salt
- Freshly ground black pepper
- 6 large garlic cloves, finely chopped
- 2/3 cup pitted kalamata olives, quartered lengthwise (3 ounces)
- 1 1/2 cups water, divided
- 1 1/4 cups panko (Japanese bread crumbs)
- 5 tablespoons extra-virgin olive oil, divided
- 5 tablespoons Dijon mustard
- 2 tablespoons finely chopped fresh rosemary
- 1/4 cup finely chopped flat-leaf parsley
- Special equpment: Kitchen string; large (18- by 13-inch) rimmed baking sheet; large heavy roasting pan; instant-read thermometer
- Heat oven to 500°F with rack in middle.
- Make a deep cut into the top side of tenderloin, about 4 inches from tail end, to facilitate folding the tail end under the roast to give the meat a more uniform thickness. Tie roast at 1-inch intervals with kitchen string.
- Cook pancetta in a large rimmed baking sheet in oven, stirring once, until fat is rendered and pancetta is crisp, 4 to 8 minutes. Transfer pancetta with a slotted spoon to a bowl.
- Add tomatoes and 1/4 teaspoon each salt and pepper to fat in rimmed baking sheet and stir, then roast in oven 15 minutes.
- Stir in garlic and olives and roast until tomatoes are falling apart and browned in patches, 2 to 4 minutes.
- Remove sheet from oven, then add pancetta and 1/2 cup water, scraping up brown bits.
- Lower oven temperature to 350°F.
- Toss together bread crumbs, 2 tablespoons oil, and 1/4 teaspoon each salt and pepper in a bowl.
- Stir together mustard and rosemary in a small bowl.
- Pat tenderloin dry and sprinkle all over with 1 1/4 teaspoons each salt and pepper, rubbing into meat.
- Set roasting pan over 2 burners, then add remaining 3 tablespoons oil and heat over medium-high heat until shimmering. Brown tenderloin on all sides, about 10 minutes.
- Spread top and upper part of sides with mustard mixture, then sprinkle evenly with bread crumbs. Pat lightly to adhere.
- Roast tenderloin until thermometer inserted diagonally 2 inches into center of thickest part of meat registers 120°F, 30 to 40 minutes. Transfer beef to a cutting board and let stand 15 minutes (internal temperature will rise to about 130°F for medium-rare).
- Set roasting pan over 2 burners and add remaining 1 cup water. Bring to a boil, scraping up brown bits, then stir in tomato mixture and parsley.
- Cut tenderloin into 1/2-inch-thick slices, discarding string, and serve with tomato mixture.