1. Preheat oven to 375°F (190°C) and grease a 9×13-inch casserole dish.

2. In a large skillet over medium heat, warm 1 tbsp oil and sauté cauliflower rice for 5–6 minutes until tender and lightly golden; season with salt and pepper.

3. Push the cauliflower rice aside and add remaining oil, onion, and garlic; cook 2 minutes until fragrant, then stir in mixed vegetables and cook until slightly softened.

4. In a mixing bowl, combine cauliflower mixture, shredded chicken, chicken broth, Greek yogurt, half of the cheese, and seasonings; stir until evenly coated.

5. Transfer mixture to prepared dish, top with remaining cheese and optional toppings, and bake uncovered for 20–25 minutes until cheese is melted and edges are golden.

6. Let casserole rest 5–10 minutes before serving to allow flavors to settle.