Preheat your oven to 375°F (190°C). Lightly grease a 9×13-inch casserole dish and set aside.
In a large skillet, warm a drizzle of olive oil over medium heat. Sauté the onion for 3–4 minutes until soft. Add garlic, broccoli, and carrots; cook for 5–6 minutes until slightly tender. Remove from heat.
In a large bowl, mix cauliflower rice, chicken, sautéed vegetables, Greek yogurt, mozzarella, cheddar, Parmesan, thyme, paprika, salt, and pepper. Combine thoroughly, adding a splash of milk or broth if too dry.
Transfer the mixture into the prepared casserole dish, spreading evenly. Top with extra cheese if desired. Bake uncovered for 25–30 minutes until bubbling and golden.
Let cool slightly before serving. Garnish with parsley or a squeeze of lemon for extra brightness.
Notes
Feel free to customize with additional herbs or vegetables. This dish is versatile and easy to adapt to your preferences.