- 2 packages (10 ounces each) frozen leaf spinach, thawed
- 1/4 cup fresh parsley, chopped
- 1/4 cup grated Asiago cheese
- 2 tablespoons capers, rinsed and drained
- 2 tablespoons balsamic vinegar
- 1 garlic clove, minced
- 1/4 teaspoon red-pepper flakes
- coarse salt and ground pepper
- 1 small flank steak (1 pound)
- 1 teaspoon olive oil
- Heat broiler, with rack set 4 inches from heat. Line a rimmed baking sheet with aluminum foil; set aside. Place spinach in a clean kitchen towel, and squeeze out as much liquid as possible.
- In a medium bowl, combine spinach, parsley, cheese, capers, vinegar, garlic, and red-pepper flakes. Season with salt and pepper; toss to combine. Cut and open steak.
- Cut several 12-inch pieces of kitchen twine; space evenly underneath steak. Spread spinach mixture down center of meat (see opposite). Roll steak over mixture, pressing firmly to compact the filling as much as possible; tie twine to secure roll. Cut roll in half crosswise. Place halves, seam side down, on prepared baking sheet; rub with oil, and season with salt and pepper.
- Broil until browned, 8 to 10 minutes for medium-rare; let rest, loosely covered with foil, 10 minutes. Remove string, and slice steak into 1/2-inch rounds.
Butterflying the Steak: Lay the meat on a cutting board, with the grain of the steak running horizontally. Using a long sharp knife, cut the meat almost in half horizontally, opening it like a book but stopping before going all the way through.