Pat the flank steak dry with paper towels and season both sides with sea salt, black pepper, and half of the dried oregano.

Heat 1 tablespoon of olive oil in a heavy-bottomed skillet over medium-high heat until it reaches its smoke point.

Place the steak in the skillet and sear for 4 to 5 minutes per side for medium-rare internal temperature.

Transfer the steak to a cutting board and allow it to rest for at least 5 to 7 minutes to retain juices.

In a small mixing bowl, whisk together the remaining olive oil, lemon juice, and remaining oregano to form the vinaigrette.

Slice the rested steak against the grain into thin strips.

Assemble the bowls by placing 1/2 cup of cooked quinoa in each dish.

Arrange the sliced steak, tomatoes, cucumber, red onion, and olives over the quinoa base.

Garnish with crumbled feta cheese and drizzle the lemon-herb vinaigrette over the ingredients before serving.