Ingredients

1 cup balsamic vinegar

1/2 cup plus 2 T EVOO

1/4 cup finely chopped rosemary

1 3lb porterhouse steak

2 tsp kosher salt

2 tsp coarsely ground black pepper

Preparation

  1. In a sturdy resealable plastic bag, combine the vinegar with 1/2 cup of the olive oil and rosemary. Add th steak, seal the bag and refrigerate overnight, turning the bag several times.
  2. Preheat oven to 425F and bring the steak to room temp. Heat a grill pan. Remove steak from marinade and season with salt nad pepper. Rub the side with the rmaining 2 T of olvie oil. Grill over moderately high heat until nicely charred on the top and bottom, about 5 min per side. Transfer the steak to a rimmed baking sheet and roast for about 30 minutes, until an instant read thermometer insterted into the tenderloin registers 125F. Slice the steak across the grain and serve immediately.