In a small bowl, mix together olive oil, garlic powder, onion powder, smoked paprika, oregano, salt, and pepper. Rub this mixture all over the flank steak.

Preheat a grill or grill pan over medium-high heat. Once hot, add the steak and cook for about 4-5 minutes per side for medium-rare, or until desired doneness. Remove from heat and let it rest for 5 minutes before slicing.

While the steak is resting, prepare the quinoa according to package instructions if not already cooked.

In a large bowl, combine cooked quinoa, cherry tomatoes, cucumber, red bell pepper, red onion, feta cheese, olives, and parsley. Drizzle with lemon juice and toss gently to combine.

Slice the rested steak against the grain into thin strips.

To serve, divide the quinoa salad among bowls and top with sliced steak. Garnish with additional parsley if desired.