Ginger-Marinated Pork Tenderloin

    1 2/3 cups chicken broth (13 1/2 fl oz)
    1/4 cup soy sauce
    1/4 cup packed brown sugar
    3 tablespoons ketchup or 2 tablespoons tomato paste
    3 tablespoons finely grated peeled fresh ginger
    3 garlic cloves, minced
    1 tablespoon cider vinegar or balsamic vinegar
    1 (3/4-lb) pork tenderloin
    1 tablespoon olive oil

Whisk together 2/3 cup broth, soy sauce, brown sugar, ketchup,
ginger, garlic, and vinegar and pour into a large sealable plastic
bag. Add tenderloin and seal bag, then marinate, chilled, turning bag
over occasionally, 2 hours.

Bring tenderloin to room temperature, about 1 hour. Put oven rack in
middle position and preheat oven to 425F.

Pat tenderloin dry and reserve marinade. Heat oil in a 12-inch
ovenproof skillet over moderately high heat until hot but not
smoking, then brown tenderloin on all sides, turning with tongs,
about 3 minutes total. Transfer skillet to oven and roast pork until
thermometer inserted diagonally into center of meat registers 155F,
12 to 15 minutes. Transfer to a cutting board and let stand, loosely
covered with foil, 10 minutes.

While meat is roasting, pour marinade through a fine-mesh sieve into
a small saucepan and boil until reduced to about 1/3 cup, 10 to 15
minutes. Stir in remaining cup broth and bring sauce to a simmer.
Serve slices of tenderloin with sauce.