Grease a 9 x 13-inch baking dish or spray with nonstick cooking spray.
In the prepared dish, toss chicken with lemon juice, olive oil, parsley, oregano, thyme, smoked paprika, seasoned salt, cumin, onion powder, garlic powder, black pepper, turmeric, and cayenne. Let the chicken sit and marinate in the herbs and spices at room temperature for 30 minutes while you preheat the oven. Preheat the oven to 375°F (190°F).
Add the uncooked rice, zucchini, and chicken broth to the pan with the chicken. Stir to combine. Cover tightly with foil. Make sure to cover your dish tightly so that none of the liquid or steam escapes during cooking. The rice needs to absorb the liquid as it bakes.
Bake for 45-50 minutes for metal pans or about 50-60 minutes for glass or ceramic pans, until most of the liquid is absorbed and the rice is tender. The total cooking time will vary based on a number of factors, including the type of pan that you use and your individual oven. Glass or ceramic baking dishes will take longer than metal pans, for instance. To know when your casserole is done, taste a bite of the rice. The rice should be tender. Use a fork to stir and fluff the rice. Taste and season with additional salt and pepper, if desired. Serve the chicken and rice topped with tzatziki, fresh herbs, and lemon.