Make the marinade. In a bowl, whisk lemon zest and juice, olive oil, minced garlic, oregano, cumin, salt, and pepper.
Taste and adjust salt or lemon.
Prep the chicken. Pat chicken dry and cut into large chunks or leave whole. Add to the marinade, toss to coat, and refrigerate for at least 30 minutes (ideally 2–4 hours). Don’t skip the rest—it boosts flavor and tenderness.
Cook your grains. Prepare rice or quinoa according to package directions. Fluff with a fork, season lightly with salt, and drizzle with a bit of olive oil for extra flavor.
Make the tzatziki. Grate the cucumber on large holes, then squeeze out extra water with your hands or a clean towel.
Stir together yogurt, cucumber, lemon juice, olive oil, grated garlic, dill, salt, and pepper. Chill until serving. It should be creamy, not watery.
Prep the veggies. Halve tomatoes, slice onion and bell pepper, and chop cucumber.
Pit and halve olives if needed. Crumble feta. Set aside.
Cook the chicken. Heat a large skillet over medium-high.
Add a splash of olive oil, then cook chicken 4–6 minutes per side (or 5–7 minutes total if using chunks) until golden with an internal temp of 165°F/74°C. Let rest 5 minutes, then slice.
Assemble the bowls. Add a scoop of rice or quinoa, top with chicken, then arrange tomatoes, cucumber, onion, bell pepper, and olives. Spoon on tzatziki and finish with feta and fresh herbs.
Add lemon wedges for brightness.
Optional extras. Serve with warm pita, a dollop of hummus, or a drizzle of olive oil. For heat, add red pepper flakes or pepperoncini.