Flank Steak
1 1/2 cup plain non-fat Greek yogurt
2 tablespoons olive oil
2 cloves garlic, pressed or very finely minced
1 tablespoon lemon juice
3 lbs extra-lean flank, hanger or skirt steak, trimmed
2 tablespoons extra-virgin olive oil, for cooking
1/2 teaspoon kosher salt (to taste)
Freshly ground black pepper (to taste)
Whisk yogurt, olive oil, garlic, lemon juice, and salt in a medium bowl to combine. Transfer marinade to a 1-gallon zipper bag along with the steak. Press out any excess air and seal bag. Transfer the steak to refrigerator to marinate for a minimum of three hours but preferably overnight, turning bag occasionally.
Remove the steak from refrigerator and bring to room temperature, about 1 hour, before cooking. Pat dry. Heat olive oil in a large cast iron skillet or griddle over medium high heat until smoking. Meanwhile, remove the steak from the marinade and pat dry, discarding marinade. Season the top of the steak generously with kosher salt and freshly ground black pepper.
Place the seasoned side directly into the skillet and season the remaining side with salt and pepper; do not move the steak once it hits the pan or a good sear will not develop. Once the steak has formed a crisp, dark golden crust, flip and continue cooking until an instant read thermometer reaches 128°F. Transfer the steak to a cutting board, loosely tent with foil, and allow to rest for 10 minutes; the steak will continue cooking from residual heat to a perfect medium rare (135°F).
For the most tender bites, rotate the steak on the cutting board so that you will be slicing perpendicular to/against the grain running through the meat. Position your knife at a 45-degree angle from the board and slice the steak on the diagonal into razor thin pieces. Transfer the slices to a serving platter and drizzle with any residual juices. Season with additional salt and pepper if necessary. Serve with yogurt horseradish sauce and/or blue cheese sauce.
Yogurt-Horseradish Sauce
2 cups plain non-fat Greek yogurt
4 garlic cloves, pressed or very finely minced
2 tablespoons prepared horseradish, plus more to taste
2 heaping tablespoons minced chives
1 teaspoon freshly squeezed lemon juice
1/4 teaspoon freshly ground black pepper
Kosher salt, to taste
Whisk all of the ingredients in a medium bowl to combine. Chill for a minimum of 1 hour to allow flavors to marry. Taste and adjust flavors before serving.
Blue Cheese Sauce
4 ounces (about 1 cup) blue cheese, crumbled
1/3 cup plain non-fat Greek yogurt
1/2 teaspoon Worcestershire sauce
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