Gyros

Thinly slice the red onion and cucumber and add it to a large mixing bowl. Fine chop the parsley and add it to the bowl as well. Add in the red wine vinegar and oregano. **Salt to taste**

In a blender add feta, garlic, yogurt, and a splash of water. Blend on high-speed until smooth. Stream in the oil and another splash of water and continue to blend until combined. Strain the sauce through a fine mesh strainer into a small bowl and whisk until homogenous. Season to taste with salt. Refrigerate until ready to use.

Whisk together the spices in a small bowl until evenly combined. Pat the flank steak with a paper towel until dry. Cut the meat into two evenly sized pieces, and season both sides generously with the spice mixture. Heat a cast iron skillet or grill pan over medium high and grease with cooking spray. One at a time, place the flank steak on the skillet and sear for 3 minutes. Flip, and sear for an additional 2-3 minutes for medium rare. Remove the steak from the pan and let it rest for 2-3 minutes. Repeat with the second piece of flank steak. Slice your steak into thin strips against the grain.