For the vinaigrette:
- 2 tablespoons tomato paste
- Juice of 1 small lemon
- 1 scant tablespoon prepared horseradish
- About 1/2 tablespoon Worcestershire sauce
- About 1/2 cup extra virgin olive oil (EVOO)
- 1 tablespoon flat leaf parsley, finely chopped
- Lots of black pepper
For the salad:
- 1 romaine heart, chopped
- 1 endive, chopped
- 4 small stalks celery, thinly sliced on an angle
- 1 1-inch-thick flatiron or flank steak (1 1/2 pounds)
- Salt and pepper
- Caperberries or sliced large green olives with pimento, for garnish
Heat a grill pan or griddle to medium-high. Combine the tomato paste, lemon juice, horseradish and Worcestershire in a bowl. Whisk in the EVOO, then the parsley; season with black pepper.
Combine the romaine, endive and celery in a large bowl.
Add the steak to the grill pan, season with salt and pepper and cook, turning occasionally, until the center is pink, 12-15 minutes. Let the meat rest, loosely covered with foil, for about 10 minutes, then slice across the grain.
Toss half of the dressing with the salad. Serve the sliced steak on top and drizzle with the remaining dressing. Sprinkle with the caperberries or olives.