Preheat your oven to 375°F (190°C) and grease a 9x13-inch baking dish with non-stick spray or olive oil.

Spread uncooked white rice evenly across the bottom of the prepared baking dish.

Pour chicken broth generously over the rice, ensuring it is fully submerged.

Distribute the cooked chicken evenly on top of the rice layer.

Evenly distribute the diced cucumber, finely chopped red onion, halved grape tomatoes, and Kalamata olives over the chicken layer.

In a separate bowl, combine the Greek-style tzatziki sauce with garlic powder, dried oregano, and a pinch of salt and pepper. Mix well.

Spread the tzatziki mixture evenly over the layered ingredients.

Sprinkle crumbled feta cheese generously over the tzatziki layer.

Cover the baking dish with aluminum foil and bake for 45 minutes.

After 45 minutes, remove the foil and bake for an additional 10 minutes to let the feta turn golden.

Once out of the oven, let the casserole cool for a few minutes before serving. Garnish with freshly chopped parsley.