Cook Quinoa: Rinse quinoa and cook it with water or broth. Heat until it boils, then cover and cook on low for 15 minutes. Fluff with a fork.
Prepare Chicken: Season chicken breasts with salt and pepper. Grill or pan-fry until cooked, then slice.
Assemble Bowls: Divide quinoa into four bowls. Add grilled chicken, cherry tomatoes, cucumber, olives, red onion, feta, and greens.
Drizzle and Serve: Drizzle olive oil and tzatziki over each bowl. Season with salt and pepper to taste.
Enjoy: Serve immediately and enjoy a fresh, healthy meal!