Cook the Quinoa: In a medium saucepan, combine the rinsed quinoa and water or chicken broth. Bring to a boil, then reduce heat to a simmer, cover, and cook for 15 minutes, or until the liquid is absorbed. Fluff with a fork and set aside.

Marinate and Cook the Chicken: While the quinoa cooks, combine the chicken cubes, olive oil, lemon juice, minced garlic, oregano, salt, and pepper in a bowl. Let it marinate for at least 10 minutes. Heat a large skillet over medium-high heat and cook the chicken for 6-8 minutes, until golden brown and cooked through.

Prepare the Vegetables: Chop the cherry tomatoes, cucumber, red onion, and Kalamata olives as directed. Set them aside in separate containers if you're meal prepping.

Whisk Together the Dressing: In a small bowl, mix together the Greek yogurt, grated cucumber, minced garlic, fresh dill, and lemon juice. Season with salt and pepper to taste.

Assemble Your Power Bowl: Start with a bed of quinoa. Top with the cooked lemon herb chicken, fresh veggies, crumbled feta, and a generous dollop of tzatziki dressing. Serve immediately or pack for later!