In a mixing bowl, whisk together the olive oil, dried oregano, garlic powder, salt, and pepper until well combined. Add the chicken breasts to the bowl, ensuring they are evenly coated with the marinade. Cover and let the chicken marinate for at least 30 minutes at room temperature, or refrigerate for up to 2 hours to deepen the flavor.
Preheat your grill or a skillet over medium-high heat. When hot, add the marinated chicken breasts. Cook for about 6-7 minutes on each side, or until the chicken is cooked through and the internal temperature reaches 165°F (75°C). Once done, remove the chicken from the grill or skillet and allow it to rest for 5 minutes to retain juices before slicing.
While the chicken is cooking, take a large mixing bowl and combine the cooked quinoa or couscous with the halved cherry tomatoes, diced cucumber, thinly sliced red onion, halved kalamata olives, and fresh lemon juice. Gently toss the ingredients together until well mixed, ensuring every component is coated with the lemon juice for added zest.
Carefully slice the grilled chicken into strips. In each serving bowl, create a base layer of the quinoa or couscous mixture. Top this with the sliced chicken, followed by a generous crumble of feta cheese. Finish with a sprinkle of freshly chopped parsley for a pop of color and flavor.
Serve the Greek chicken bowls warm.
Notes
For an extra touch, drizzle with additional olive oil and garnish with a lemon wedge.