Preheat oven to 375°F (190°C). Grease a 9x13-inch baking dish.
In a saucepan, combine rice and chicken broth. Bring to a boil, then reduce heat, cover, and simmer for 15–20 minutes until tender.
Melt butter in a skillet over medium heat. Sauté onions and garlic until soft (3–4 minutes).
Stir in flour to form a roux. Gradually whisk in heavy cream until smooth. Add cheese, salt, pepper, and paprika. Stir until cheese melts.
In a large bowl, mix cooked rice, diced chicken, peas/carrots, and cheese sauce. Transfer to the baking dish.
Cover with foil and bake for 25 minutes. Uncover and bake 10–15 more minutes until bubbly and golden.
Let cool 5 minutes before serving. Garnish with parsley if desired.
