Makes 4 servings. 
Ingredients
1 beef flank steak (12 ounces) 
For marinade: 
1/4 cup lemon juice
1 tablespoon olive oil
2 teaspoons fresh oregano, rinsed, dried and chopped (or 1/2 teaspoon dried) 
1 tablespoon garlic, minced (about 2 to 3 cloves) 
For yogurt sauce: 
1 cup cucumber, peeled, seeded and chopped
1 cup nonfat plain yogurt
2 tablespoons lemon juice
1 tablespoon fresh dill, rinsed, dried and chopped (or 1 teaspoon dried) 
1 tablespoon garlic, minced (about 2 to 3 cloves) 
1/2 teaspoon salt
Directions
<ul>
 <li>For the marinade, combine lemon juice, olive oil, oregano and garlic in a large bowl. </li>
 <li>Lay steak in a flat container with sides, and pour marinade over the steak. Let the steak marinate for at least 20 minutes (or up to 24 hours in the refrigerator), turning several times. </li>
 <li>Combine all the ingredients for the yogurt sauce. Set yogurt sauce aside for at least 15 minutes to blend flavors. (Sauce can be prepared up to 1 hour in advance and refrigerated.) </li>
 <li>Preheat oven broiler on high temperature, with the rack 3 inches from heat source. </li>
 <li>Broil steak for about 10 minutes on each side (to a minimum internal temperature of 145 degrees). Let cool for 5 minutes before carving. </li>
 <li>Slice thinly across the grain into 12 slices (1 ounce each). </li>
 <li>Serve three slices of the steak with 1/2 cup yogurt sauce on the side. </li>
</ul>
Try it in a sandwich with pita bread, lettuce and tomato.
Nutrition information
Serving size: 3-ounce steak, 1/2 cup yogurt sauce. Amount per serving: 181 calories, 7g total fat (2g saturated fat), 36mg cholesterol, 9g carbohydrates, 21g protein, 0g dietary fiber, 364mg sodium. 
Source:<a target="_blank" href="https://healthyeating.nhlbi.nih.gov/recipedetail.aspx?linkId=1&amp;cId=1&amp;rId=2"> National Heart, Lung, and Blood Institute</a>

Greek-style flank steak with tangy yogurt sauce