Beef Tenderloin Sandwiches with Herb Mayonnaise
These beef sandwiches are wrapped in parchment, tied with baker's twine, and transported in a baking dish that doubles as a serving tray. The watercress is packed separately so that it stays crisp.
- 1 tablespoon vegetable oil
- 1 center-cut beef tenderloin (2 pounds), trimmed of excess fat, tied
- Coarse salt and freshly ground pepper
- 8 to 10 cloves Roasted Garlic
- 3/4 cup mayonnaise
- 1 tablespoon fresh lemon juice
- 2 tablespoons finely chopped fresh flat-leaf parsley
- 1 tablespoon finely chopped fresh thyme
- 1 tablespoon finely chopped fresh marjoram
- 1 baguette, halved horizontally and cut crosswise into 3 pieces
- 2 cups watercress, preferably baby
Preheat oven to 425 degrees. Heat oil in a large ovenproof skillet over medium-high heat. Generously season beef with salt and pepper. Add to skillet, and brown on all sides, about 10 minutes total. Transfer skillet to oven.
Roast until beef registers 130 for medium-rare, 20 to 25 minutes. Let beef stand for 20 minutes. Cut into 1/4-inch-thick slices.
Meanwhile, mash garlic with a fork in a small bowl. Stir in mayonnaise, lemon juice, and herbs. Season with salt and pepper. (Garlic-herb mayonnaise can be stored in the refrigerator for up to 1 day.)
Spread 1 tablespoon of the mayonnaise onto each bread slice. Top with beef. Just before serving, add watercress. Season with salt and pepper.