Marinate the chicken: In a bowl, mix olive oil, lemon zest and juice, garlic, oregano, cumin, smoked paprika, salt, and pepper. Add chicken, toss to coat, and marinate for at least 30 minutes or up to 8 hours in the fridge.
Cook the grains: Prepare quinoa, farro, or brown rice according to package directions.
Fluff with a fork and let cool slightly so it doesn’t wilt the greens.
Make the yogurt sauce: Stir together Greek yogurt, lemon juice, olive oil, garlic, dill, salt, and pepper. Taste and adjust seasoning. Chill until ready to serve.
Prep the veggies: Dice cucumber and bell pepper, halve tomatoes, slice red onion, and chop herbs.
Pat the cucumbers dry with a paper towel to reduce extra moisture.
Cook the chicken: Grill, pan-sear, or bake. For grilling or stovetop, cook over medium-high heat 4–6 minutes per side until the internal temperature reaches 165°F/74°C. Let rest 5 minutes, then slice.
Assemble the bowls: Add a base of grains and greens.
Top with sliced chicken, cucumber, tomatoes, red onion, bell pepper, olives, and feta. Spoon on yogurt sauce. Finish with chopped dill and parsley.
Finish and serve: Drizzle with a little olive oil, add a squeeze of lemon, and season with a pinch of salt and pepper if needed.